Sunday, January 17, 2010

When to start seeds

I was asked by a reader, when is a good time to start seeds and whether I was too early by starting seeds in January?

I live in the Los Angeles area, and I have noticed over the last several years that the weather warms up in the March time frame. Also, in March, I start seeing Tomato plants (both Cherry and regular) for sale in nurseries in my area, along with other vegetable plants. You can even buy Winter Melon plants for sale at San Gabriel Nursery in March.

So my strategy is to have seedlings ready to transplant outdoors in March. Last Year, I had Cherry Tomato seedlings in the ground by February 21 (see this blog entry), which is a few weeks early. But, I had Cherry Tomatoes ready to eat 3 months later (see this blog entry).

It typically takes about 6 weeks under Grow Lights for my seedlings to be big enough to transplant. So, if I start seeds on January 1, I would have seedlings in mid February. A bit early, but this gives me margin for error. As you see in this blog entry, the Cherry Tomato seeds that I started on January 1, did not germinate and I had to restart new seeds.

If you don't have Grow Lights, you can start seeds on a windowsill that faces the Sun most of the day. The most important thing is that the seeds stay warm. Most seeds need to be in soil that is around 75 degrees F in order to germinate. You can buy a heating mat, if you have trouble keeping your potting mix at the right temperature.

I find that if I keep my seeds starting kits right under my Grow Lights, the heat from the Grow Lights is sufficient to warm up the soil.


  1. Hi SoCal Gardener,
    Thanks for your response! I spent last week getting my seedling trays and lights set up. Still not quite there yet. Knowing you're only two weeks into starting your seedlings is encouraging me to get a move on it :-). Last year was my first year gardening in So. Cal. (San Clemente) and I bought all my seedlings. This year I want to experiment with a variety of plants (as you have blogged about in the past).

    This past week I measured the temperature of my garage and it averaged about 60 degrees F (+/-). It is cold in my garage because the sun doesn't hit that side of the house. I'm thinking of getting heat mats, but, that'll take time since I'll have to find them locally or order online. It might be worth it because I've heard that soil temperature is usually 10 degrees F lower than the temperature around it.

    Also, do you grow successive batches of tomatos seedlings or do you grow all you'll need at one time? Last year I had to build all my raised beds and didn't get tomato seedlings planted until May. They did great and were quite prolific. Once Fall approached they pretty much stopped producing. So, had I started them earlier (as you are suggesting) would I have had tomatos producing longer? Or do tomatos produce only for so long based on when they're started?

    Do you also recommend starting cucumber and squash seedlings now?

    Sorry for all the questions, but, I'm trying to maximize my yields by taking advantage of the unique growing season here in So. Cal.. Thanks for the links to your previous blog posts. I didn't know that about fish bone meal helping the tomato's blooms. I have regular bone meal and I know that'll help.

    I'm starting to see tomato seelings for sale at my local Lowes. I am tempted to buy some, but, I think with all the rain anticipated that it is just too soon.

    Happy gardening,

  2. To see the answer your tomato question, see this blog entry.

    Regarding your cucumber and squash question, I have never grown cucumbers, but I believe squash is the same family as Winter Melons. I find that starting Winter Melons in January allows me to have more and bigger fruit.

    I would not buy any Tomato seedlings now. It is still too cold and there is not enough sun for the plants to grow properly. You will end up with leggy plants that will not be able to produce much fruit. Better to wait until March to transplant seedlings in the ground.