Next month:
April 2006

Raindrops keep falling on my garden

Soaked soil from endless rains getting you down? Me too. It was clear today, but tomorrow, here we go again! If you are ready to plant and the rain keeps falling, try tarping the bed you hope to plant next. Use one of those blue tarps people put on leaky roofs. Put a bucket or a large pot upside down in the middle of the bed, put the tarp over it, and then weight the edges with stones or bricks. Remove the tarp on sunny days, to allow for drying. Put it back on when rains threaten. This trick can speed drying of a small area considerably.

Soil is dry enough to dig or sow seeds when a handful squeezed together breaks up easily if you prod it with a finger. If your finger just makes a dent in a ball of sticky soil, it is too wet to work.

Soil that is sandy can be worked when it is wetter, since it still falls apart easily, but clay has to be fairly dry or you will cause damage to its tilth. Adding organic matter (compost or aged manure, for example) allows clay soils to be worked when they are holding more water.

If you build a better gopher trap...

...will the world beat a path to your door? I suspect that many people, mostly those who haven’t watched treasured plants become gopher food, are squeamish about controlling the little gnawers with traps. But for those who must do it as part of their job, and for home gardeners who have lost too many treasured plants, a new trap described in last Saturday’s S.F. Chronicle, should be a welcome improvement. It’s called a cinch trap, and unlike the traditional Macabee trap, doesn’t require extensive digging to locate a tunnel. If you can find an active surface opening, you can just insert the cinch trap there. The article describing this new trap is an interview by Deborah K. Rich with Thomas Wittman, part owner of Gophers Limited, in the Santa Cruz area. You can read it at:

     I found that cinch traps are widely available for purchase on the web, and there is even a little video showing how to set one at this address:

     For an article from UC Davis about gopher control, including a list of the repellent techniques that don’t work, such as planting gopher purge, inserting vibrating devices in the soil, and putting chewing gum in their tunnels, check out:

I promised a soil temperature reading today. On Saturday, March 4th, the soil thermometer read 38 degrees F. Could br a fluke. Maybe the thermometer was inserted deeper than last week, or in a colder place, but it shows that the soil is definitely not warming up yet. And with all the cold rain that is continuing to fall, I don't suppose it will warm up anytime soon. My records show that last year at this time the soil temperature in that garden was 52 degrees F. A bit different from this year!

When to plant seed?

As the days get longer, gardeners become eager to put seeds in the ground, but run the risk of putting them in too soon. Seeds of some kinds of plants can grow while the ground is still cold, but others require warmer soil. Soil temperature is taken with a soil thermometer, in the morning, in the shade, and inch or so below the surface. Three weeks ago, the soil in the teaching garden at City College of San Francisco was 46 degrees F. Last week it was 42 degrees, made lower by the cold storm we had the previous week. This goes to show that the warming of soil is in spring is not necessarily a steady process. What will it be tomorrow? I will report.

In soil this cold, the snap pea seeds are germinating, though they aren't all up yet after 3 weeks. In soil at 60 degrees, we'd have seen them all in about a week. Warm season crops, like tomatoes or peppers, might not come up at all in soil this cold, so are best started indoors at the nice warm 80 degrees they prefer.

For a nice short article on what might have caused your seeds not to come up, see an article on the website of Ed Hume Seeds. 

First Day Blog

Wednesday will be garden tip day from now on. Today, however, is the first day of the rest of my blog, and so my first topic is the blog itself.

     Monday will be gardening news, Wednesday, a gardening tip or idea, Friday, a link to some useful information. Plus, count on plenty of talk about all kinds of topics you care about if you are a Northern California gardener (or one in a similar climate), including the weather, the plants, the bugs, and the bigger issues that affect or concern gardeners. I will also keep you posted about lectures I will be giving, and other selected events of interest to gardeners.

     On this Sunday, March 5th, I will be speaking at Gamble Garden Center, at 1431 Waverly Street in Palo Alto, about the plants in my most recent book, Wildly Successful Plants: Northern California. The talk and slide show will be from 2 to 4 p.m. I will answer questions and sign books after the talk. You can learn learn more about the talk and Gamble Garden Center at

     March is the month of the San Francisco Flower and Garden Show. I will be attending the opening gala, the press reception, walking the show, and will be speaking there on Friday, March 17th at 6:30. (If you are there on Friday, stop by and say hello after the talk.) I'll report on it all. (You can link to the show at, and learn more about the complete schedule.) My lecture will be about Mediterranean Climate Food Gardening, how to take full advantage of our mediterranean climate to have a year round harvest of garden delicacies.

     In my garden: My first Pacific Coast hybrid iris of the season opened this week, a blue one, and a hard rain is falling on it tonight. In the food garden, 'Sugar Sprint' peas are just breaking through.