Timing is everything
As much as warm winter days (and glossy seed catalogs) may tempt us, Morgan Hill gardeners are wise to wait. According to the almanac of farming fame, Morgan Hill's last frost date is Feb. 15, while the National Oceanic and Atmospheric Administration (NOAA) warns that gardeners have a 10 percent chance of freezing temperatures as late as March 20! Starting too soon is simply a waste of time and seed.
Before planting, decide what you want to grow. Browsing seed catalogs can be intoxicating. Rather than ordering everything that looks good, find plants that are suitable to your microclimate, won't need a lot of water, and are non-invasive.
Read the label
Most seed packets are a wealth of valuable information that includes an image of the plant, description, and any special needs. Labels also list the year, timing, planting depth and spacing, thinning, sunlight, and watering needs of each plant. Use this information and save it for future reference.
Some seeds can be planted directly into the ground. This is called direct sowing. While all growing areas will serve your plants better if they are regularly fed with aged manure and compost, this is especially true for seeds and seedlings. They have a lot of work ahead of them and need all the nutrients they can get their little root hairs into. Most seeds are better off started in small pots filled with high-quality potting soil or starter mix.
Starting seeds in small containers is the easiest way to begin. Placing one seed into each small container allows tiny roots to develop unchallenged. It also makes transplanting less stressful. You can reuse plastic seed starting pots, called "cell flats" from when you buy seedlings. Remember to clean and disinfect flats to avoid spreading pests or diseases. You can make biodegradable planting containers from paperboard egg cartons, newspaper, or toilet paper tubes, or you can buy seed starter pots. Take-out food containers, with clear plastic lids, can also be used for seed starting. The plastic covers keep warmth and moisture in.
Once you have collected your seeds, containers, and potting soil, you are ready to plant. Labels made from Popsicle sticks are very handy, too. Labeling is important because many young plants are difficult to tell apart until they are long past the transplanting stage. Follow these steps for successful seed starting:
- Fill all containers loosely with potting soil, tamping it down gently.
- Place one seed in the soil to the depth specified on the packet.
- Add a dated plant label to each pot.
- Place flats on a water-resistant surface that will receive six to eight hours of sunlight each day, where they will be safe from slugs and snails.
- Gently and thoroughly water the flats. For seeds left on the soil surface, use a mister to water, to avoid washing them away, or pushing them too deeply into the soil. Soil should be kept moist, but not soggy, until the first true leaves are seen.
- Some plants, such as peppers, may need extra heat from a heating mat.
Now the seeds are started and waiting begins. Use this time to prepare your garden beds, raised beds, containers, towers, and other planting areas so they will be ready when it is time for transplanting,
Stop by the Spring Garden Market from 9 a.m.–2 p.m., April 14 at Martial Cottle Park for spring planting needs.
by UC Master Gardener Kate Russell
This article first appeared in the March 14 – 27, 2018 issue of Morgan Hill Life.
Benefits of seed starts
Some plants, such as lettuce, have tiny seeds that need light to germinate. Planting these directly in the ground often leads to losses due to wind dispersal or rotting under too much soil. Starting these plants in containers makes it easy to monitor them and keep the soil moist until the seeds sprout.
As seedlings grow, they can become root bound, which means the roots start wrapping around the inner wall of the container. Before this happens, you can up-pot or transplant those seedlings. Up-potting means moving a seedling from a small container to a slightly larger one. Transplanting means moving the plant to where it will live out its life.
When not to transplant
Plants that are fruiting, flowering, infested, or infected should generally not be transplanted. New transplants need to be able to focus on building strong root systems. Also, just as some people are more sensitive than others, some plants do not take kindly to being transplanted. The following plants should be sown directly into the ground whenever possible: artichoke, beans, beets, butternut squash, carrots, corn, cucumber, dill, melons, onions, peas, radishes, summer squash and zucchini.
How to transplant seedlings
For many vegetables, you can transplant seedlings with the first leaves below the soil line. Very often, these meristem tissues will transform into root tissues, adding nutrients to the plants. Once the seedlings are a couple of inches tall, prepare their new home, making sure the soil is loose.
The South Bay's heavy clay can form an impenetrable barrier to new roots if it is left smooth from a trowel or shovel. Be sure to rough up the edges of the planting hole. Then, follow these steps to successfully transplant the seedlings:
1. Place your hand over the container with the plant between your fingers.
2. Gently turn the pot on its side or upside down, tapping the bottom with your other hand to knock the soil loose.
3. Cup your first hand to hold onto as much of the soil as possible.
4. Examine the roots and spread them out if they have started wrapping around themselves.
5. Slowly turn your hand, allowing the root system to roll into the hole.
6. Ensure all roots are covered with soil. If peat pots were used, make sure all of the peat is covered, as well.
7. Gently pat the soil down to eliminate any big air pockets. (Most roots don't like being exposed to air.)
8. Water thoroughly.
Caring for new transplants
New transplants should be treated gently for a few days. To help a young seedling thrive in its new environment, in a process called ecesis, be sure to:
Harden off seedlings before transplanting; water regularly, allowing the soil to dry out between waterings; do not use insecticidal soap or other treatments right away; feed transplanted seedlings with fish emulsion or phosphorous a few days after their ordeal; protect seedlings against cutworm damage by inserting a paperboard ring a couple of inches into the soil; provide wind protection by cutting the bottom out of large plastic jugs and placing them over vulnerable plants.
Visit the South County Teaching and Demo Garden, at St. Louise Hospital, 9400 No Name Uno. For more information, visit Events and Classes or call (408) 282-3105 between 9:30 a.m. to 12:30 p.m.
by UC Master Gardener Kate Russell
Photo: Copyright © 2016 The Regents of the University of California. All Rights Reserved.
This article first appeared in the May 24 – June 6, 2017 issue of Morgan Hill Life.
Soil temperatures might still be too cool
Like many of you, I bought my tomatoes and peppers at one of the Master Gardener's spring market sale. It was so cold and rainy that I wasn't overly enthusiastic to get out and work in the garden so I grouped my plants together, sat them next to the garden shed for a little warmth and protection and decided to let them be.
Then, ignoring what experience has taught me, I decided to put them in the ground. And I paid a price for my impatience.
Planting too early in cooler temperatures can cause stunted growth, wilting, surface pitting, foliage necrosis and increased susceptibility to disease. Low soil temperatures can stunt plant growth and prevent root development. Most summer vegetables like soil temperatures of between 55 and 65 degrees.
Because my plants had just come from a greenhouse, where they were pampered with lots of light, water and warmth, they really needed to be hardened off before planting. Hardening off means to keep your seedlings in protected area, such as a porch or garage, and gradually acclimate them to their new environment, placing them outdoors in a shady spot for a couple of hours and slowly increasing the time. Plants that aren't properly hardened off are much more susceptible to sun and windburn as well as breakage.
We also recommend planting your seedlings into larger containers as soon as you bring them home.
So what happened when I didn't follow the prudent planting process? Well, one of my tomatoes snapped in half and I have a couple of peppers that look very much like the sad little tree in “A Charlie Brown Christmas.” I'll be starting over with some new seedlings and a bit more patience.
Tips for planting
- Plant your tomatoes deep (up to leaves you didn't pinch off)
- Amend soil with a high-quality compost (if needed)
- If planting in containers or raised beds, add slow release, organic fertilizer and compost
- Add tomato cages when you plant, if you wait until they need the support you can damage the roots
- And remember, peppers and tomatoes need 6 to 8 hours of sun. They also like well-draining soil and a pH of 6.5-7.0.
- Mulch around plants to help retain moisture and cut down on weeds.
- To avoid fungal issues such as fusarium and verticillium wilt, don't plant in the same area for 3 years, if possible.
- To avoid blossom end rot, make sure to provide consistent and deep watering.
- One of the most common tomato ailments is tobacco mosaic virus so don't smoke in or near your garden.
- Look for plants that are labeled disease resistant.
- The rains are tapering off, so make sure to keep young plants well watered. Peppers like to be kept evenly moist, but once tomatoes and peppers start fruiting you can significantly cut back on their water.
by UC Master Gardener Rebecca Jepsen
Photo: Rebecca Jepsen
This article first appeared in the April 30 issue of the San Jose Mercury News.