Your Garden … with Jenny Redfern: Start seeds soon if you’re dreaming of peppers and tomatoes in your garden
Published in the February 17 – March 1, 2016 issue of Morgan Hill Life
By Jenny R. Redfern
But wait, isn’t it too early to start spring and summer vegetable seedlings? Not if you have a spot near a window that you can keep warm, even while the rain is still coming down in South County.
Control the environment
Time your seeding to begin six to eight weeks before the plants will go into sun-warmed, prepared soil with a temperature of more than 60 degrees. (My garden bed at the Morgan Hill Community Garden reaches 60 in mid to late April.) Then control the environment for your seeds by starting with clean pots and fresh potting soil. Choose containers at least two to three inches deep, such as recycled plastic plant six-packs, small recycled pots, or plug trays, with drainage holes. Wash them with a weak bleach solution to remove dirt and pathogens.
Do not fill the pots with dirt from your garden. Even if it has already grown great crops, it may carry soil-born disease that can kill off seedlings. Seedlings require consistently moist soil with enough air spaces to allow root hairs to flourish. Loosely fill the rinsed containers three-quarter full with moist bagged potting mix that includes organic compost and slow-release fertilizer. And check the back of the seed packet for the expected germination rate, usually less than 100 percent.
Plant the seeds
Level the soil in the containers and gently press the seeds onto the moist surface, one per plug or one inch apart in larger containers. Sprinkle a quarter inch of soil or vermiculite over the seeds, and moisten the surface. Set the containers in trays to catch drips — recycled plastic food containers work well. Place a clear cover over the container for the first week or until the seeds germinate and you see green sprouts poking through the soil. For small containers, use clear plastic wrap and a rubber band, or recycle the clear plastic covering from your take-out lunch. And don’t forget to label the seeds. Used Popsicle sticks work fine.
Then control the warmth and light. If your seeding spot gets sufficient light but still feels cold, invest in a heating mat — my seedlings sprout in much less time on a warm mat.
Once the seeds have germinated, make sure they get full sun all day or are exposed to grow-lights. When the first set of true leaves has emerged, thin the seedlings to one-and-a-half to two inches apart, so that they do not compete for nutrients and moisture. Seedlings in plug trays should be up-potted to larger containers to develop larger root systems.
Hardening off and planting
Ten to 14 days before transplanting, accustom the seedlings to the great outdoors. Set out the containers on your picnic table or patio on sunny, warm days, and bring them in at night. For the last few nights, leave the trays outside, but make sure they are protected from birds and squirrels looking for fresh greens.
When the seedlings have sturdy stems and the garden soil is warm, check the small print on the back of the seed packet, then plant according to the directions for spacing, and apply organic fertilizer as needed. Then exercise patience and good gardening practices — add compost to the soil, mulch the soil around the plants, pull weeds, pick off damaging insects, keep the soil moist – until those vegetables and flowers match their beauty shots in the seed catalog.
Jenny R. Redfern is a Master Gardener for Santa Clara County. She wrote this column for Morgan Hill Life.