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September 2007
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November 2007

Bur Clover

Sometimes, when I send a photo to go with my column (for the SF Chronicle, at, there isn't room for it. I guess I had too much to say. So when that is the case, I will try to put those photos on my blog.


Today's photo is of bur clover, a weed that is related to other clovers and to peas and beans. The bur is a little pod, like a bean pod, that is curled up and has prongs along the edge to catch on fur or clothing. I've picked them up on cloth shoelaces. The plant has tiny yellow pea-type flowers and, like beans or white clover, each leaf has three leaflets. At the base of each leaf there are a pair of little wing-like structures called stipules. (If you see this plant, get out a hand lens and check out some of these details. They are really interesting when seen larger.) The plant lies fairly flat to the ground, so mowing often doesn't do much to control it. In fact, if you have it in a thinly covered grassy area, and mow the area, you will favor it over the grasses. If the grasses were to remain unmowed and grow over its top, the bur clover would be shaded out.

The writer whose question I answered in the column today had been told to pull bur clover out. This can work if you keep at it, since it is an annual plant, growing only from seeds. Pulling when the plant is small or when soil is moist or both works best. It seems to sprout at different times of year. I have the mature plants in the photograph in the garden now, but I see it in summer as well, from seeds that germinated in the spring.

The solution I gave in today's column was for a property that was not going to be actively gardened. Judith Lowry, of Larner Seeds ( suggested a cardboard mulch covered with purchased soil. In the purchased soil, she suggested sowing seeds of red fescue. This is a solution intended for California, near the coast, where red fescue is native. I'm sure there would be other best choices of grass for other parts of the world.

Chard Leafminers

Ccsf_garden_sept_9_044_72 My Golden Gate Gardener column in the Home Section of the SF Chronicle this morning (accessible at was about the leafminers that attack Swiss chard, beets, and spinach. I thought you'd like to see a photo to help identify this Swiss chard pest. Leafminers are larvae of a fly. They lay tiny white eggs on the leaf undersides. When the maggots hatch, they eat a hole in the leaf surface and start eating out the leaf--the part of the leaf between the upper and lower epidermises (epidermi?). Some leafminers, like the ones that infest columbine, eat winding trails in the leaf, but the one shown here usually creats big ugly blotches.

What to do? I have been fighting these critters for several years, removing leaves with damage, spraying with summer oils (purchased at nurseries) to kill the eggs. (The oil product I use is based on canola oil, with a sticker-spreader, so should be nontoxic to people.) Even tried Spinosad, a new product, containing an exudate of a bacterium, that is registered for use by organic farmers. Some neem oil products are also registered for use on this pest and crop.

But the problem is that the maggot isn't damaged much by chemicals unless they penetrate into every cell, and products that do this would render the plants inedible. The catch 22.

What else to do? You can try to kill the pupae. They fall to the soil and later emerge as adult flies. The life cycle repeats about monthly from the end of March to mid October in San Francisco's climate, with the winter generation overwintering as pupae. I plan to keep the chard I am growing until March (may as well, it won't have the damage then). In March, I will take it all out and dig the soil to turn up any pupae it contains where they are likely to dry out or be damaged, or maybe (hopefully) eaten by birds. (In summer, when the soil is warmer, you could apply beneficial nematodes to the soil. They are a bit pricy, but should eat this and other pests.)

Then, no chard, beets, or spinach all summer. (There is plenty else to grow.)

In late summer, I shall start some chard seed indoors. When it is a month or two old, I will plant it in the garden. If it is ready to plant, but still before mid-October, I will cover it with row cover (a thin spun-polyester material that lets light and water through) making sure it is secured at the ground so flies can't fly in. When the weather turns cool enough to kill the flies, off will come the row cover. Then I should have chard unmolested until the following March.

Has anyone had any better ideas for dealing with this annoying pest of chard, beets, and spinach?

End of Summer in SF Gardens

Summer is drawing to a close in San Francisco, even though the calendar clearly shows that it is autumn. We've been having our late warm weather, an echo of the heat of Southern California, though, thankfully, so far without the hot winds or fires. In our food gardens, at this time of year, we are harvesting the last of summer's crops still, and beginning to get the crops of fall.

October_07_066_copy  Imagine my surprise, when I was photographing in my community garden, when I found that someone in the garden has several large eggplant plants that are setting fruit. The plants are nearly two feet tall. This one is setting round white fruits, tinged with lavender.

October_07_065_copy And here is another with long fruits, green now, but probably they will turn purple. I have tried eggplants, and seen others do so, in SF, but rarely have I seen any fruit setting. These must have been blooming on particularly warm nights. The last one I saw with fruit had only a tiny fruit in mid-November!

October_07_079_copy Nevertheless, fall is indeed on its way. The cole crops I planted at the college garden in mid August are continuing to develop. This is 'Ruby Ball' cabbage. The head will be an ordinary red cabbage, but the hues of the leaves, which are blue green with lavender veins, are so lovely.

October_07_078_copy Another beautiful leaf is that of this speckled oakleaf lettuce. I don't know the name of the variety. It was part of a mix, I think. But it is tender and mild, despite the warm weather we've been having, and adds that certain something to our salads.

October_07_058_copy And, finally, one more shot of that giant, edible-podded Brazilian pea. I thought I should shoot it with my hand in it, so you could see how big the pod is. And also, I put in a flower, which really isn't red (roxa? someone help me with the Portuguese) but is lavender and purple.

Brazilian Pea 'Torta de Flor Roxa'

This year I grew some seed that was given to me, by I forgot who, for "Brazilian peas." I had never heard of these before, and had no idea what kind of pea they were, but they grew and produced pods. Now I am learning a little about them.

Ccsf_garden_sept_9_064_copy The pods are extremely wide, something like 1 1/4 inch, with the peas forming along one side. I wondered if the pods were edible, and found out that they are! That is, they don't have a fibrous lining that you can't chew, like shelling peas. So these seem to be a sort of snow pea. The plants are about 2 1/2 feet tall, growing on a string trellis that I made (you can see the green string in the photo at left.)

Ccsf_garden_sept_9_061_copy I am growing the few pods that I have to maturity, so I can grow more plants next year. My web search found one fairly complete description of this pea variety, on the website of the Seed and Plant Sanctuary for Canada ( From their home page, click on "beans" in the database list, and you will find Brazilian peas included. They say "best when pods are full," which seems to mean to eat them after the peas partially form,  rather than when the peas are still tiny, which is when you would eat Asian-type snow peas. From the seed sanctuary site, I found, which seems to be their commercial arm. They sell the seeds, and call them Ervilha Torta Flor Roxa. What does that mean? Flat peas with red flowers (a wild guess--the flowers are two-toned purple). Unfortunately, this company doesn't sell seeds in the U.S., due to too many customs restrictions they say.

Using Google Image Search, I found a photo that looks just like my peas, on the website,  which seems to be a Brazilian seed company. They mention a pea Erhilha Torta de Flor Roxa in the text.

So, I shall grow these out and multiply them. Does anyone know any more about these peas, botanically or culinarily? Or a better translation of the name? Or how they got to Brazil? Or whether they are grown anywhere besides Brazil?

Early October in the Demo Garden

We are starting to feel the first chills of fall here in San Francisco, warm in the daytime, but brisk at night. The garden at the college continues to grow and bear food. We are having a potluck next week in class, and different students are using some of the harvest in dishes to bring. Among them are zucchini, leeks, and beets.

Ccsf_garden_sept_9_023_copy Here are some of the beets. We planted them in the spring, and probably they should have come out by now, but we are looking forward to beet pickles.

In the long bed planted with cole crops, the little seedlings, all looking alike are beginning to show their differences.

Ccsf_garden_sept_9_038_copy The cabbage is low and wide, with short stems on the leaves. This one is 'Parel' an early variety, rated at 50 days. In the case of these crops, you calculate the days to maturity from the date of setting out the seedlings, at about 6 weeks old. We set these out in the first week of August, so now, in the first week of October, we are a bit behind the promised schedule, but the central leaves are beginning to curl over the forming heads.

Ccsf_garden_sept_9_037_copy_2 This is Brussels sprouts 'Vancouver' which is rated at 90-100 days. Notice how much taller it is and the long stems on the leaves. In another month or two, we should be eating little sprouts.

FInally, here is a mature purple kohlrabi, of the variety 'Kolibri'. We ate several of these in class last week. It is right on schedule, ready to eat in 60 days after transplanting. They were crisp, sweet, and delicious, but, alas, you lose the color when you peel these purple gems to eat them. Too bad, but still, very good.

Ccsf_garden_sept_9_029_copy All of the cole crop varieties in this bed were grown from seed purchased from Territorial Seed Company in Oregon.

A Talk in Orinda: Mediterranean Garden Society

I'll be giving a public lecture and slide show for the Mediterranean Garden Society on Saturday, October 27th, 1:30 pm, at the Orinda Public Library, 24 Orinda Way, in Orinda, CA. I'll have books for sale and signing after the talk.

My topic will be the history and culture of the plants I wrote about in the book Wildly Successful Plants. I consider these plants regional garden treasures--easy to grow, drought tolerant, mostly deer resistant, and beautiful. They include annuals, bulbs, perennials, succulents, and shrubs. Many are from mediterranean climate areas of the world, though some are from other (often surprising) places.

You can read more about my talk, and find a link to a Google map, at (the page of the Northern California Branch of the Mediterranean Garden Society). If you live nearby, hope you can come and say hello.

If you come to this talk, you can also learn more about the MGS, which is an international group formed to study and enjoy plants of the world's mediterranean climates. See their informative website at They'll be having an international conference next year in Monterey, CA. Stay tuned for more information about that.