Golden Gate Gardener

An Appreciation of Tigridia--A Summer-Blooming Bulb

In my dry-summer  San Francisco garden, the spring bloom is wonderful, but not as much blooms in summer. So in July and August, when spring's show has faded, I welcome the dramatically large and vivid blossoms of Tigridia pavonia. I like the color they add to my summer garden and the fact that the dramatic flowers face upward, so I see the fronts of the flowers when I look down from an upstairs window or even when I am standing over the flower bed. Each flower lasts only a single day, but each plant has several flowers, so the show goes on for weeks.

Tigridias grow from small bulbs, which are frequently offered in nurseries. They also grow easily from seed, and often bloom the first year from a seed. though it might take two years for a seed-grown plant to bloom. Where winter temperatures do not drop below 30 degrees F, and if soil drainage is good, they are likely to come back year after year. 

Tigridia flowers are triangular, on stems 1 1/2 to 2 feet tall. They are 3-6 inches across, typically 4 inches or more. They can be red, pink, yellow or white, usually with a contrasting, spotted center. As you might guess from the scientific name, it is sometimes called a "Tiger flower," though the typically spotted center looks more like a leopard or jaguar to me. Another common name is Mexican shell flower, reflecting the Mexican origin of the plants, which grows from Mexican lowlands to its higher elevations. 

I saved seeds from yellow flowers only and grew an all-yellow planting in my front garden, where I avoid pink flowers, allowing only white, yellow, orange, red, and blue. I grew the seedlings I hoped would have yellow flowers in a container for the first year, and when I saw they were, transplanted them to the front garden. This was a successful experiment, so now I have a yellow selection in front, and another that is blooming in red, pink, or yellow in the back yard. 

Here is a close up of the center of the flower, showing the pistil and stamens. The tall pistil has a branched stigma on top. The lower part of the stamens appear to be pressed closely against the lower part of the pistil, with the 3 pollen-bearing anthers near the stigma. I have not seen what pollinates Tigridia, but clearly some insect does so, aiming for that dramatically spotted center. The plants bear many seeds, in a long pod. When the pod turns brown and the top opens, one can cut the pods and simply shake them upside down to let the seeds fall out.

The Pacific Bulb Society says that the exact origin of this plant are unclear because the Aztecs ate the bulbs, so they moved it around by cultivating it. (It is unusual for a member of the Iris family, the Iridaceae, to be edible, so I will not try to eat it until I learn more.) After it blooms, and I have cut any seedheads that I want to save, I will cut the stems low to the ground and let the bulbs remain dormant all winter. 

This is not a mediterranean plant, but, like Mexican hen and chicks (Escheveria) it is from a location that has summer rain, but is dry in winter. Still, like that plant, it can adapt to our gardens if it is given some water in our dry season and is growing in soil that drains well, like my San Francisco sandy loam. I don't water the plants after they bloom and they will become dormant over winter. 

In spring, the new leaves will emerge, pleated fans that look like palm seedlings. The plants are not very leafy, saving their energy for those dramatic flowers. If I have seed, I will sow it in late winter, indoors, probably on my little heat mat. I may grow the plants in containers for the first year or just plant them out in the garden and see what happens.

The Availability of Watsonia borbonica corms

Watsonias--Wildly Successful Plant of Late Spring

May 22, 2012   And again in January 2021

I ran the following post, as you can see from the date above, in 2012. It has attracted many comments. I am running it again, below, in order to write about a couple of issues raised by a number of commenters. First, read the post, below, which explains Watsonia culture and shows some photos of the plants blooming in our neighborhood. However, readers cannot find the bulbs for sale. The most likely reason for this is that Watsonias are out of fashion. When gladiolus bulbs began to be actively hybridized, gardeners were dazzled by the variety of color, and bicolors that were being bred, so fewer people were interested in Watsonia, which blooms only in white, salmon, pink, and red. I grow Watsonia borbonica because I live in  a Mediterranean climate, similar to that of its native land of Mediterranean South Africa, where the mild rainy winter stimulates the leaves to grow and the dry summers allow the plants to rest a bit before fall rains start leafy growth again. Also, when I have tried to grow Gladiolus, they have suffered from a rust fungus disease. I have seen Gladiolus in nearby gardens that were damaged by thrips insects. Watsonias never seem to have diseases or insect damage. Gladiolus, nevertheless, is probably a bigger seller than Watsonia, rendering Watsonia bulbs, or corms, scarce in nurseries. There is also a second reason for Watsonia's lessened popularity. That is that there is an invasive Watsonia. It is called Watsonia meriana, a summer-dormant species described as bearing dull red-orange, purple, or white flowers in late spring. A variety of this species, W. meriana bulbifera, bears bulblets, or cormlets,  on its flowering stems that can reproduce the plant, giving it two means of asexual reproduction (the cormlets could roll away and start new colonies!). While this species is not on California Invasive Plant lists, it has been seen growing wild on roadsides and in fields in Sonoma and Mendocino counties. It is also a pest in Australia, and may partly explain the difficulty of locating Watsonia borbonica corms for sale here and there, since nurseries may confuse it with this other Watsonia and be afraid to sell it. So the first point is that it is hard to find the corms for sale, probably for 2 reasons: Plants go in and out of fashion, and this one has been out of style, and also, the habit of just using its genus name has allowed it to be confused with another, potentially invasive member of the same genus. 

So, what to do if you long for this tall, beautiful, low-maintenance plant. I suspect that your best bet is to notice some growing in a garden in the spring and ask the gardener if you can have some corms when they are dormant in the summer. Since the plants you see were probably planted some time ago, when they were being sold, and since they become crowded and bloom less after they have grown in the same place for several years, chances are there will be plenty of corms to spare. I see Watsonias in a number of gardens in San Francisco, and have seen them in old gardens of Pacific Grove (next to Monterey). Probably in areas where they will thrive on the California west coast, you will see some in bloom this spring. Meantime, I can only hope that nursery propagators are listening.

You can read more about Watsonias and 49 more easy care, drought tolerant plants in my book Wildly Successful Plants: Northern California.       

 

In April and May I look for Watsonias. I love these big, graceful plants, with tall stems of trumpet-shaped flowers. These easy-to-grow bulb plants are one of South Africa's best gifts to Bay Area gardeners. They are among the 50 plants I featured in my book Wildly Successful Plants: Northern California, as very well suited to our gardens and easy to grow. (See cover, at right) They thrive in cool or hot summer areas. I don't know of an insect pest or a disease that troubles them, and snails don't seem interested either. 

The red one in the two photos above is a hybrid, one of several usually available in nurseries for fall planting.  

After you plant the bulbs (correctly, they are corms), the leaves begin to grow with the first rains. They usually don't need any irrigation beyond rainfall to mature and bloom. Even last winter, which was rather dry, I didn't water mine, though I might do so in a really, really dry winter. After weeks of glorious mid- to late spring bloom, they die back in early summer. You don't have to water them in summer either. These are truly drought-tolerant plants! If the soil is well-drained, they won't mind a little summer water, but if kept too moist, they won't bloom as well the following year.

            The reason Watsonias do so well here is that they are from the Cape Region of South Africa, which has a similar rainfall pattern to ours. The regions where they grow have poor, sandy soil, so our rather poor soils are not a problem, though they can take moderate fertility, if you want to dig in a little compost. They stand up to wind and cool temperatures. They thrive in foggy microclimates. Full sun is best near the coast, but half-day will do. If you garden in a hotter inland microclimate, they will appreciate the hot soil while they are dormant. The spring-blooming Watsonias described here are hardy to 10° F.

            It's best to cut the flower stalks after they bloom and, in mid to late summer, cut brown leaves to the ground, before new green ones start to grow, so that they won't distract from next year's show. The deadheading and cutting back is really the only annual care they need.

            Watsonias are grand at the back of a border, where their 5- 6 foot tall flower stalks will be seen over other plants. Another way to grow them is behind a hedge, so they stand above it when in bloom, disappear when they die back. Or mix them into a narrow border with other plants of similar height--shrubs or other tall perennials. In addition to ornamenting the garden, Watsonias make good cut flowers.

            Most of the Watsonia plants I see growing are hybrids, with peach, pink, or red flowers, which are readily available at nurseries for fall planting. I also see the pink or white-blooming ones that represent the species, Watsonia borbonica, especially in older gardens.

I think the pink one in the three previous photos is the species, Watsonia borbonica. It is described as having "violet" stamens, and these look violet to me.

This white one may be Watsonia borbonica ardernii, a subspecies that was discovered in the wild.

            Plant the corms about 4 inches deep and 6 inches apart. You can plant in a circular area to get a nice clump, or could plant in a row.

            While the plants will thrive with little care, if you have time, and want to groom your plants to keep your garden looking at its best, here is what to do:

            While the plants are blooming, remove spent flowers every few days. They will fall off in your hand at a slight pull. When the top flower of the central stalk of flowers has bloomed and faded, cut that stalk off where it joins a lower flower branch that still has buds or open flowers. (You will need hand pruners for this, as the stalks are tough). When all of the side stalks have finished blooming, cut the entire flower stalk short enough that the cut end won't be visible above the leaves.

            When all of the flower stalks have been cut, you can ignore the plant until all the leaves turn brown, or you can go out every couple of weeks and remove brown leaves. It is up to you. But when all the leaves are brown, cut them as short as you can. You will need sharp pruners to do it. Don't wait until the green "swords" of the new leaves push through in fall, or you will have a devil of a time avoiding injury to the new leaves!

            That's about it, until, a number of years later, you might see that the clump is blooming less, or only near the edge, or that it is a bit too wide for its location. Then you might want to go out when the plants are dormant, in summer, and either remove some corms near the edges to reduce the clump size, or actually dig the whole thing up and replant corms.

            Either way, you will have some corms to plant elsewhere or to share. Full sized corms are 2-3 inches across and will probably bloom the following spring. Smaller ones (cormlets) will take 2 or more years to bloom. If you dig the whole clump, you will probably have more corms than you know what to do with, and may want to discard the smaller ones. (Or maybe go into the Watsonia corm business.)

            One more tip. You can grow Watsonias in a big pot, say 15 inches across for a group of corms, but in a pot you will need to give them a bit more care. From the time the plants start to grow to when blooms are starting to fade, fertilize lightly from time to time, and water regularly. You don't want the mix to be soggy, but unless rain is keeping it wet, water when the top inch is dry.

Learn about 49 more easy, beautiful garden flowers in Wildly Successful Plants: Northern California.

 

In April and May I look for Watsonias. I love these big, graceful plants, with tall stems of trumpet-shaped flowers. These easy-to-grow bulb plants are one of South Africa's best gifts to Bay Area gardeners. They are among the 50 plants I featured in my book Wildly Successful Plants: Northern California, as very well suited to our gardens and easy to grow. (See cover, at right) They thrive in cool or hot summer areas. I don't know of an insect pest or a disease that troubles them, and snails don't seem interested either. 

The red one in the two photos above is a hybrid, one of several usually available in nurseries for fall planting.  

After you plant the bulbs (correctly, they are corms), the leaves begin to grow with the first rains. They usually don't need any irrigation beyond rainfall to mature and bloom. Even last winter, which was rather dry, I didn't water mine, though I might do so in a really, really dry winter. After weeks of glorious mid- to late spring bloom, they die back in early summer. You don't have to water them in summer either. These are truly drought-tolerant plants! If the soil is well-drained, they won't mind a little summer water, but if kept too moist, they won't bloom as well the following year.

            The reason Watsonias do so well here is that they are from the Cape Region of South Africa, which has a similar rainfall pattern to ours. The regions where they grow have poor, sandy soil, so our rather poor soils are not a problem, though they can take moderate fertility, if you want to dig in a little compost. They stand up to wind and cool temperatures. They thrive in foggy microclimates. Full sun is best near the coast, but half-day will do. If you garden in a hotter inland microclimate, they will appreciate the hot soil while they are dormant. The spring-blooming Watsonias described here are hardy to 10° F.

            It's best to cut the flower stalks after they bloom and, in mid to late summer, cut brown leaves to the ground, before new green ones start to grow, so that they won't distract from next year's show. The deadheading and cutting back is really the only annual care they need.

            Watsonias are grand at the back of a border, where their 5- 6 foot tall flower stalks will be seen over other plants. Another way to grow them is behind a hedge, so they stand above it when in bloom, disappear when they die back. Or mix them into a narrow border with other plants of similar height--shrubs or other tall perennials. In addition to ornamenting the garden, Watsonias make good cut flowers.

            Most of the Watsonia plants I see growing are hybrids, with peach, pink, or red flowers, which are readily available at nurseries for fall planting. I also see the pink or white-blooming ones that represent the species, Watsonia borbonica, especially in older gardens.

I think the pink one in the three previous photos is the species, Watsonia borbonica. It is described as having "violet" stamens, and these look violet to me.

This white one may be Watsonia borbonica ardernii, a subspecies that was discovered in the wild.

            Plant the corms about 4 inches deep and 6 inches apart. You can plant in a circular area to get a nice clump, or could plant in a row.

            While the plants will thrive with little care, if you have time, and want to groom your plants to keep your garden looking at its best, here is what to do:

            While the plants are blooming, remove spent flowers every few days. They will fall off in your hand at a slight pull. When the top flower of the central stalk of flowers has bloomed and faded, cut that stalk off where it joins a lower flower branch that still has buds or open flowers. (You will need hand pruners for this, as the stalks are tough). When all of the side stalks have finished blooming, cut the entire flower stalk short enough that the cut end won't be visible above the leaves.

            When all of the flower stalks have been cut, you can ignore the plant until all the leaves turn brown, or you can go out every couple of weeks and remove brown leaves. It is up to you. But when all the leaves are brown, cut them as short as you can. You will need sharp pruners to do it. Don't wait until the green "swords" of the new leaves push through in fall, or you will have a devil of a time avoiding injury to the new leaves!

            That's about it, until, a number of years later, you might see that the clump is blooming less, or only near the edge, or that it is a bit too wide for its location. Then you might want to go out when the plants are dormant, in summer, and either remove some corms near the edges to reduce the clump size, or actually dig the whole thing up and replant corms.

            Either way, you will have some corms to plant elsewhere or to share. Full sized corms are 2-3 inches across and will probably bloom the following spring. Smaller ones (cormlets) will take 2 or more years to bloom. If you dig the whole clump, you will probably have more corms than you know what to do with, and may want to discard the smaller ones. (Or maybe go into the Watsonia corm business.)

            One more tip. You can grow Watsonias in a big pot, say 15 inches across for a group of corms, but in a pot you will need to give them a bit more care. From the time the plants start to grow to when blooms are starting to fade, fertilize lightly from time to time, and water regularly. You don't want the mix to be soggy, but unless rain is keeping it wet, water when the top inch is dry.

Learn about 49 more easy, beautiful garden flowers in Wildly Successful Plants: Northern California.

Daffodil Aftercare

    Daffodils thrill us with cheery yellow, white, or bicolor flowers in February, or even January. They often do naturalize in our region, coming back to bloom again year after year.

            If they are growing in pots they are unlikely to bloom the following year, and are probably best discarded after you enjoy the flowers. If the daffodils are growing, instead,  in your garden, you have a good chance of getting them to naturalize.

Your first post-bloom task is to remove any stems that bore flowers. This keeps the plant from wasting energy on them, especially should the spent flowers form seeds.

Your second task is to care for the post-bloom leaves. They need water and unshaded light until they start to die back, but not fertilizer. (Add fertilizer as you plant the bulbs in fall and work a little into the soil in future autumns.)

Do not tie daffodil leaves in knots. I don’t know how this common practice began, but it limits the plants’ ability to photosynthesize, so they can’t make good bulbs to bloom the following spring.

Finally, keep the soil where daffodils are planted relatively dry in summer. Daffodil ancestors are from summer-dry Mediterranean regions. The bulbs may decay in wet summer soil.

Gardeners experience two problems in following this advice. They are: 1. unsightly leaves after bloom and 2. Finding a place where daffodils will not be too wet in the summer.

If these problems seem insurmountable, you could treat the bulbs as annuals. Just dig them out, as you would non-naturalizing tulip plants, discard them, and buy new ones in fall.

To hide the leaves as they decline, you can use companion plants. Good choices include many small flowering annual plants, including nigella, viola, sweet alyssum, or, my favorite, the pink and lavender-flowered Virginia stock (Malcolmia maritima). Taller plants, such as California poppy or nasturtium, must be managed so they don’t over-shade the daffodils.

While daffodils can take some summer water, don’t try  to naturalize them in a bed you will be watering amply in summer. Make sure nearby plants are somewhat drought-tolerant, and if you use drip irrigation, make sure you don’t have an emitter right next to a daffodil. You can put daffodil bulbs among other summer-dry plants, such as succulents, for a fresh and attractive combination.

I took this photo in the wonderful garden of Harland Hand, in on a west-facing hillside in El Cerrito, some years ago, when he was alive and tending his own garden. It changed the way I understood daffodils. They are well adapted to a climate with wet winters and dry summers. So are the Babiana bulbs blooming in the lower right. The succulents in this small bit of garden are adapted to low moisture in general, but can tolerate our winter rain if the soil is well-drained. 

Bay Area Rose Pruning Clases January 2016

    I prepared the following list of rose pruning workshops for my January, 2016 column, which was to run on January 3, but it did not. Then it was to run on January 10, too late for Jan. 9-10 workshops, but at least helpful for the rest of the month. But it was dropped from my column. So here it is, in hopes that it might help at least a few people learn to prune their roses. While any pruning demonstration will help you learn the techniques you need, if you want some first-hand experience, note especially the hands-on pruning experiences, in San Mateo's Central Park January 16, and in the San Jose Heritage Rose Garden every Saturday for the rest of January and the first half of February.

Is Your Future Rosy?

Love roses? Learn rose pruning and care at classes or hands-on workshops taking place in January around our region. Free unless otherwise noted.

Berkeley: Berkeley Horticultural Nursery, 1310 McGee Ave., berkeleyhort.com, 510-526-4704; Rose Pruning Classes: Saturdays, January 9 and 23 at 10 AM.

Cupertino: Yamigami Nursery, 1361 S. DeAnza Blvd., yamigamisnursery.com, 408-252-3347; Winter Rose Care Classes: Saturday, January 9 at 10 AM, Sunday January 17 at 11 AM. (20% off coupon for day of class included)

Marin: Marin Art and Garden Center, 30 Sir Francis Drake Blvd., Marin Rose Society, marinrose.org, 415-457-6045; Annual Pruning Demonstration: Tuesday, January 12, 7:30 PM. (nonmembers $5.00)

San Jose: Guadalupe River Park Heritage Rose Garden, 412 Seymour St., heritageroses.us/PruningLessons.htm, 510-526-4704 (Volunteer Coordinator Jessica Gonzales); Supervised Pruning: Wednesdays and Saturdays, January to mid-February, 8:30-11:30 AM. (Bypass shears and leather gloves provided.)

San Mateo: Central Park Arboretum, 50 East 5th Ave., sanmateoarboretum.org/classes-special-events/, 650-579-0536 x3; Rose Pruning Symposium: Sunday January 10, 1-3 PM, $15 ($10 for members, reservation required)

Help Prune Central Park's Rose Garden: Saturday, January 16, 10-Noon. (Instruction included--bring shears and gloves.)

San Francisco:

Rose Garden, Golden Gate Park, Pruning Demonstration by the S.F. Rose Society: Jan 9, 10 AM-1 PM (or January 16 in case of rain).  

Flowercraft Garden Center, 550 Bayshore Blvd, flowercraftgc.com, 415-824-1900; Rose Clinics: January 16 and 17, 11 AM-Noon, February 13 and 14, 11 AM -Noon.

Controlled Chaos: Welcoming Self-Seeded Plants Into Your Garden

In this month's SF Chronicle column (which will appear December 13, 2015) I reviewed a book called Cultivating Chaos: How to Enrich Landscapes with Self-seeding Plants. Every vegetable gardener knows that some vegetables self-seed in gardens. The mustard or arugula we didn't pull out before they set seed, the last beans, hiding in the foliage until they ripen and drop, the parsnip we let bloom to attract beneficial insects. These all will result in little surprises in the following year. With our long California seasons, with plenty of time for seeds to ripen, we probably see more volunteer crop seedlings than would gardeners in short-summer climates.

(Self-seeded arugula with Daffodils, in February. A free salad green that decorates the garden until you eat it up.)

               What do we do about it? Depending on our needs, we may let the volunteer grow and eat it. Or, if it is in the way, we may move it, or if that isn't possible, because it will not transplant well, or if we have too many seedlings of it, we pull it out. No problem. We usually kind of like it that nature has given us something we might eat without having to sow the seed. So it is a short leap to enjoying volunteers in our flower gardens.

               The Cultivating Chaosbook is a celebration of ornamental plants that grow from naturally dropped seed, as opposed to seed we replant each year. It will be an inspiration to those who want to have a truly beautiful ornamental garden that embraces some of these plants. It includes many photos of handsome gardens or parts of gardens using self-sowing plants, tips on using them well in gardens, and a plant encyclopedia to illustrate and discuss the merits of a number of plant candidates.

(I shot this image at Annie's Annuals. This nursery, in Richmond, CA, is a good source of plants that will reseed, such as these red poppies. They are at anniesannuals.com.)

                Here I must acknowledge that some gardeners are afraid of self-seeding plants. It has been a fashion recently to plant home gardens that are like the gardens of a commercial establishment in that the plants have been chosen to grow slowly, need little pruning, and stay put. A thick mulch is applied to keep weeds down, and any wayward seeds usually perish in the mulch. It's called low-maintenance gardening, and I suppose it is, but oh, how I would miss the serendipity of an old-fashioned garden flower bed.

               The authors of Cultivating Chaos understand that one does not want a garden to be 100% chaos. They say the trick to creating a pleasing garden design with self-seeding flowers is to contrast their relative chaos with "clearly defined architectural forms and areas of quiet that are the result of traditional garden planning."

               Yes! I knew this when I decided what I wanted in my own garden. It needed enough structure created by hardscape that some of the planted areas could be more random (or chaotic), with only an occasional formal row of some plant to add a modicum of order. Broken concrete and used bricks create low retaining walls and a patio, with some paths made of concrete pavers or decomposed granite. Now I have to decide how much self-sowing to allow. I have learned, as did the authors of Cultivating Chaos, that much of what goes on to manage the potential chaos is removal of unwanted seedlings.

               Removing self-seeding plants is weeding, really, but what you remove is often, and, as the process continues, more often, a flower rather than a true weed. (If there is bare earth, and even if there is a mulch, really, there will be weeds. So one might as well be weeding out flower seedlilngs as weedy plants with no ornamental value.)

               I must say here that my book, Wildly Successful Plants: Northern California, features a number of self-seeding ornamentals that thrive in our regional microclimates. I grow many of these in my own garden--including columbine, blue nigella Kenilworth ivy, feverfew, linaria, cineraria, nasturtium, Johnny-jump-up, and California poppy. I do buy plants and seed, but I depend on self-sowers to fill in between them and bloom each year without having to be purchased or sown.(And I also have volunteer parsley, chervil, arugula, potatoes, an occasional parsnip.)

(A self-seeded Alpine strawberry, golden feverfew, purple cineraria, and columbine fill in this corner of my garden.)

               And, as I said earlier, many gardeners are afraid of self-sowers, so they are afraid of my book. A sad fact, since they are losing access to so much useful information, including information on which of the featured plants are deer tolerant, snail tolerant, drought tolerant (most), or attractive to humming birds.

             The book Cultivating Chaos skips lightly over potential problems and over the chance of plants escaping into wildlands. However, in Wildly Successful Plants, I don't skip these hard parts, but have delved into them thoroughly so that a gardener can make decisions that are responsible for our region and for an individual garden.

               One of the main principles of responsibility is that plants act differently in different regions. I was surprised to find lady's mantle (Alchimella mollis) listed in Cultivating Chaos as a self-seeder, as it has never done that in my garden. Nor has blanket flower (Gaillardia). On the other hand, they say that Mexican daisy (Erigeron karvinskianus) can be expected to self-sow only in dry locations with sandy soil. Here, in a dry summer Mediterranean climate, that plant reproduces like crazy (though the variety 'Spindrift', mentioned in Wildly Successful Plants, is said not to produce seed.)

               There is also a question of whether a plant could become a wildland weed. Again, only a paragraph of warning in Cultivating Chaos, but a careful analysis in Wildly Successful Plants. My analysis is possible in part because I am writing about a specific region, whereas Cultivating Chaos, which was written by Germans and which tries to be more universal in coverage, can't deal with the fact that fennel and ox-eye daisy, which they recommend, are nasty weeds here, while lady's mantle, as I mentioned, doesn’t seem to self sow at all.

(California poppies are featured in both Cultivating Chaos and Wildly Successful Plants, but I've explained in Wildly Successful Plants that the native in the Central California Coast region is this two-toned variety.

               To be a wildland weed, incidentally, a plant needs not only to self-sow, but to be able to compete in regional undisturbed or lightly disturbed wildland habitats. This ability varies by plant and by region, and I've analyzed it carefully before suggesting each plant in Wildly Successful Plants.

               The strength of the book Cultivating Chaos lies not in its analysis of using self-sowing plants responsibly, but in its photos. They give design ideas that will inspire you to want a bit of chaos in your garden. There are all-the-same-color flower plantings and ones with bold contrasting color schemes; informal gardens with only paths through the self-sown beds; and gardens in which chaos plays against formal hedges and hardscape. There are self-sowers peeking up through pavers and ornamenting dry-stone walls. There are photos of plants that have formed handsome seedpods, backlit to show their edges. The photos make me want to create ever more lovely self-seeded chaos in my garden.

Full bibliographic Info:

Cultivating Chaos: How to Enrich Landscapes with Self-Seeding Plants, Jonas Reif, Christian Kress, with photos by Jürgen Becker, Timber Press, 2015.

Wildly Successful Plants Northern California, Pam Peirce, with photos by David Goldberg, Sasquatch Books, 2004.

(Seedpods of some common self-seeding flowers.)

Some Resources for Waterwise Gardeners

This is not meant to be a complete list, by any means, but here are a few publications and links that will be useful if you are selecting plants for a waterwise garden.

WUCOLS stands for Water Use Classification of Landscape Plants. This project, sponsored by UCDavis, California Dept of Water Resources, California Center for Urban Horticulture, lets you find out the water needs of over 3,500 landscape plants in six different regions of California. The most recent version WUCOLS IV,can be accessed at the following address:

http://ucanr.edu/sites/WUCOLS/   Click on "Plant Search" Or you can use this link: WUCOLS IV

For information on growing California Native Plants, check out the Las Pilitas web site, laspilitas.com, or use this link: Las Pilitas Nursery.

Here are links to two articles on the subject of watering trees during a drought that were recently in the San Francisco Chronicle:

Trees Out on A Limb

Watering Trees in A Drought

Finally, here is a short list of books that you will find useful as you seek ideas and plants for a waterwise garden:

California Native Plants for the Garden, Burnstein, Fross, O'Brien, Cachuma Press, 2005.Photos, text on garden uses and care.

New Sunset Western Garden Book. I think the most recent is 2012, and it does have all color photos, which are helpful, but the text of couple of editions right before this one were a little more thorough.

Plant Life in the World's Mediterranean Climates, Peter B. Dallman, University of California Press, 1998. Maps and charts show how the 5 mediterranean regions are similar and, importantly, how they differ, then explains the habitats to which many of our favorite plants are adapted.

 Plants and Landscapes for Summer-dry Climates of the San Francisco Bay Region, East Bay MUD, 2004. Inspiring photos and useful information.

The Random House Book of Indoor and Greenhouse Plants, Roger Phillips & Martyn Rix, Volumes 1 & 2, Random House,1997. Despite the name, thiese two volumes cover mostly mediterranean and other subtropical plants that we can grow outside. The photos and text about the plants in their native habitats are very useful.

Wildly Successful Plants: Northern California, Pam Peirce, Sasquatch Books, 2004.California garden history, plant origins, garden maintenance instructions, garden design, and a philosophy for a regional garden.

About the Bidens Hawaiian Flare Series

A number of readers wrote in to ask where they could purchase the Bindens varieties I wrote about in my August column. The one shown above is Bidens Hawaiian Flare series 'Red Drop'. It and other Hawaiian Flare Bidens varieties have been available to wholesalers for at least two years, but are not often to be found in local nurseries. When I saw this variety last summer at the Mendocino Botanical Garden, I asked them about it. They said their supplier was out. I neglected to find out its name, and without a name, I didn't have a way to search for it.

Then the manager of Flowercraft Nursery, in San Franciso, found it in a truck arriving from a wholesaler, thought it might be what I wanted and plucked some out for me. With the correct name, I could write about it, and with the proper name, we can ask local retailers to carry it.

A little research turns up the following information:Bidens Hawaiian Flare series was bred by Florsaika, a Japanese company see florsaika.com/bidens-hawaiian-flare/). It is available only from cuttings, and these are handled exclusively by Florexpo, a company based in Costa Rica that sells unrooted cuttings to brokers worldwide, but mostly to North America, Europe, and Japan. (See florexpo.net)  On the websites of both of these companies, you can see videos that explain their businesses.

From Florexpo, the cuttings go to brokers. Then a wholesale nursery buys them from a broker and grows the  plants up to the size retailers want. Finally, the wholesaler sends out plants, in some combination of what the retailer asks them to send and what they think a retailer will want.

Before I list a plant, I usually contact some local nurseries and make sure they are carrying it, so they won't be caught without it. But in this case, I think the plants are sleepers--great choices that have not become widely available. You might find them available locally, but if not, politely ask your local nursery for the plants by name. Tell them you'd like to have some Bidens Hawaiian Flare Series plants, now, if they can get any, next spring if they can't get them now. Then they will ask their wholesalers about the plants, and either get ones now or see if they can get a wholesaler to grow some for spring. (The nurseries that are most likely to carry these varieties are ones that buy plants from wholesalers, rather than ones that usually grow their own plants from their own seed or cuttings, since these plants have to be grown from purchased cuttings.)

Here is how Hawaiian Flare 'Red Drop' looks in my garden now (growing with blue annual Convolvulus tricolor and some chartreuse green nicotiana).

The plants growing with them are Nicotiana in chartreuse and white and annual Convolvulus tricolor (blue).

Here is another Bidens Hawaiian Flare, 'Red Star', that I found in a nursery, not realizing at the time that it was in the same series as 'Red Drop'.

It is growing here with some blue edging lobelia.

The advantages of the new Bidens varieties are, besides different colors and larger flowers than were otherwise available, that their more open, taller form allows them to drape and to mix with other plants in a border, and their height makes them more attractive to native bees and other beneficial insects.

Finally, here is a close up of the Bidens that used to be the main one available. The plant shown here is fairly young, so only has a few flowers, but when it grows larger, this plant will be a low mat covered with the one inch yellow flowers.

It is growing under a taller feverfew plant that has similar, but larger, leaves.

Help Learning to Use Plant Scientific Names

There is another post containing resources for gardeners learning to use plant scientific names. You will find it if you search for "Plant ID". I have added the following new one today:

http://oregonstate.edu/dept/ldplants/2plants.htm Searchable list of common garden plant genera. Click on a genus name to get description and links to many photos of different parts and stages of the plant. It also links to another database, this one providing a simplified plant key for woody landscape plants.

Gardening Up Close--Managing Self-Sowers, Plants with Runners, and Bulbs

Gardening: Up Close   What to do about plants that crowd eachother and themselves. 

Garden plants do not just stand still and look pretty. Not only do they grow taller, but they also leap wildly from place to place, creep stealthily outside their allotted area, and sometimes bunch up until they are so close together they can barely breathe, let alone bloom. So one of the tasks of the gardener is to serve as a plant referee. This photo shows three plants that are competing for the same space. Not only that, but one of them is competing with itself! These plants also illustrate the three main ways plants reproduce: seeds, runners, and bulbs, and how a gardener might referee their competition.   

            The blue-flowered lobelia is an annual, a plant that grows only from seed, blooms in a couple of months, and dies in under a year. It spreads in a garden by dropping seeds. They might grow where they drop or may roll or be moved by water into new places. In my garden, dropped lobelia seed doesn't grow very often, resulting in only a few random plants a year, so it doesn't make a pest of itself. I watch for the  small lobelias with their first blue flowers, and either leave them unmolested where they choose to grow, or move them to a place I prefer. I left the one in the photo alone to grow where it voted to put down its roots. I thought it a nice touch at the base of the broken concrete retaining wall next to the creeping fern.

            Then the fern began to creep toward the lobelia. Its rhizomes crept forth, forming new plantlets every few inches. OK with me, since it makes a nice backdrop for the tiny sapphire blossoms. The fern is Blechnum penna-marina, a South American species that in cool moist locations, in mild winter gardens, makes a tidy perennial patch of low, leathery leaves.This one survived in a neglected corner of my garden for several years, just getting by, but has been growing happily in the new spot to which I moved it about five years ago. It has filled in its space and slightly enlarged the area it covered.

            As this past spring progressed, the lobelia got bigger, and then the fern began to creep under and past it, into the area where I have been growing some Babiana. Babiana is from South Africa, where it blooms after winter rains and can survive the  long dry summer. The leaves that emerge with my California autumn rains grow to about eight inches tall. Then in late winter flower stems reach a foot or so tall, each bearing about a half-dozen rosy-purple flowers. Very nice on an early spring afternoon with the sun shining through.

            Spring passes, summer comes, I cut the browning flower stems, then the dying leaves. Soon there is only a tidy brown stubble, awaiting another chance to grow. The bulbs, or in this case, the similar structures known as corms, have stored up food enough to send down fresh roots when the rains begin again, to start the process over.

            Babiana has been the perfect choice for this tiny strip of rather sandy soil between the brick patio and the retaining wall. It turned out that strip was so narrow that it was very difficult to keep moist all through the summer, but since Babiana is dormant all summer, it needs zero summer water.             

            As the fern runners continue their reach, fern roots are going to tangle with the perennial Babiana corms. I have no way of knowing if the Babiana will survive this overrunning of its territory, so I must consider taking out some of the competing fern growth.

            Mediating further in the direction of fern control now is the fact that the Babiana corms, have been multiplying in their appointed spot for several years. This plant, as is the case with bulbs generally, doesn't move around, it just becomes more crowded. The plant is fighting with itself to find more room. There are more and more leafy plants each year. At first, the stand just produced more flowers, but in the past couple of years, the number of flower stems has held steady, or maybe even decreased. The Babiana is succeeding so well that it has begun to fail.

            At this point, I need to dig up all the corms and divide them. This just means separating them--they are loosely connected--and resetting the largest of the bulbs with a bit of room among them. If there are too many large ones for the space allotted, I'll have the choice of giving the planting more room or giving some of them away.

            There will also be small ones that won't bloom for two or maybe three years. These can be interplanted with the large corms in a larger area, or can be grown in an out-of-the-way place until they bloom, when you can decide where you want a new bed of Babiana. Or, they can be given to someone who wants to wait while they reach blooming size, or added to compost.          

            The questioning mind might wonder: If bulbs that grow from year to year crowd themselves up until there are few blooms, what happens in nature? In the case of Babiana, I have been told that they got their scientific name from the fact that baboons like to eat them. They dig up the corms and chomp them down, probably in the dry season when it is easier to wipe them clear of soil and they provide a welcome bit of moist food. I imagine baboons eat the biggest corms first, but miss some and especially miss the small ones, naturally thinning the lot.

            In some cases, as with Watsonias, the corms eventually form a large circular mound. If some animal begins to bite or kick out a corm here or there, and some that become detached might don't get eaten, they might roll off to a new location to start a new stand of Watsonias.

            The same goes for plants like my fern that grow from rhizomes or runners. Some foraging animal might break some off and not do a thorough job of munching all the broken plant bits, so some broken bits could roll or blow to a new place and send down roots.

            But a garden is not part of an intact ecosystem, with an equilibrium between animals and plants, so when plants are fighting it out, the gardener must step in. I now need to legislate the locations of the running fern and the clumping Babiana. Where do I want to let them be? And do I want to let the innocent lobelia, which grew from a randomly dropped viable seed right between the fern and the Babiana live out its short life in peace?

            First, I will dig up the part of the fern that has overtaken the Babiana bed, pot it up and save it for a friend who wants to grow some. Then I will dig up all of the Babiana corms and see what I have there. I will probably dig some fertilizer, a bit of earthworm compost, into the place they have been growing. Then I'll replant some of the larger corms 4 inches deep and 4 inches apart. (I looked the best depth and spacing up in a book.)  What if there are more large ones than I need for my tiny space? Hmm. Then a decision needs to be made.

            I will not disturb the part of the fern under the lobelia right now, because it is such a cheerful spot of blue! Only when it begins to fade will I decide if I have taken out enough of the fern.  

            But for a while longer, I will simply enjoy the battle, letting visitors to the garden think that this handsome plant grouping is an intentional and stable garden arrangement, created by nature and my careful planning.

I'll show that first photo again and if your eyes are sharp, you will see two other situations developing that will need attention one day.

Did you notice the different kind of fern, the one with the larger fronds, at the base of the broken concrete, just above the lobelia? There seem to have been fern spores in the crannies of the used concrete we got through Craigs List, and some of them have germinated. Chances are this wll be a large fern, too large for the space. I may not be able to priy it out to move it either, so when it starts to overwhelm the spot, I may have to just rip it out. Sigh.

And arching up into the cracks of the concrete above and to the right of that fern, you will notice the leaves of some creeping campanula that has reached down from the top of the wall. Nice now; it made a few blue flowers that were very winsome in the wall in June. But if the wall were to be covered with it you'd lose the charm of the wall. You got it, more ripping out in the offing.

 

Mendocino--Coast Botanical Garden

At the end of May, we took a trip to Mendocino, where we visited the Coast Botanical Garden. It is always a treat, in part because the plantings are lovely, and in part because there are such a variety of environments. At the front, there is a perennial garden, then cactus and succulents, trees and shrubs, water garden, woodland garden, and if you keep on walking, you enter wild land that eventually leads to a tall grassy bluff over the ocean. Below there are rocks and waves. Above, native bunch grasses and wildflowers. One year there was a sea otter in the rocks below us. This year, no such luck, but I got this shot of the California native seathrift (Armeria maritima) at the very edge of the bluff.

I knew that this species was from near the ocean, from the "maritima" in the specific epithet, but I had never pictured exactly what that could mean-right over the water as it is.

It was also fun to see all the native succulents, the Duddleyas, that grew down the rocky slopes to the water, but not possible to climb down and photograph them.

In the perennial plantings of the garden, there are both native and non-native plants. And of the natives, both species and cultivated varieties of wild species. This wonderful California poppy variety is called 'Champagne and Roses'.

And right in the front, in the window boxes of the cafe, there was this wonderful planting of bidens. Both cultivars have larger flowers than the species, and the rusty-orange one has purple leaves. I wanted it, but the nursery manager said she was not only out of it, but so were all of her suppliers! Darn!

 I was so busy taking photos that I forgot to ask the name of the cultivar, but I am hoping to find it again. Any reader happen to know what it is called?

Next post I will show some photos of plants in the town of Mendocino and the coastal trail around the city. The town is full of common and rare flowers and surrounded by a skirt of wild flowers.