See...I told you things were beginning to happen in my hill country garden! In light of the recent blizzards hitting much of country (even folks in Dallas got dumped on with a record 12.5 inches of snow a couple of weeks ago!), we here in South Texas are beginning to get serious about spring gardening.
Although it is way too early to put tomatoes in the ground, it is not too early to pot them up and put them in the greenhouse. This allows the tomatoes to grow, yet protects them from the cold until mid-March or April, when the weather stabilizes enough to safely put the plants in the garden. For me in the hills, I won't put either tomatoes or peppers in the ground until the end of April. We typically get hit with a frost in mid April. When we first moved to Boerne in 2004, I lost all my tomato and pepper plants because I planted them in the garden too early. Lesson learned. My tomatoes and peppers do not go in the ground until April 25-30.
In potting up tomatoes, the first step is selecting the variety you want to grow. I love heirloom tomatoes as much as the next foodie, but my experience has been that they just don't do well here in deep South Texas. It just gets too hot. Although Texas A&M is working on an heirloom variety that *does* well here...can't wait for that! In the past I've planted Cherokee Purple, Black Krim, Druzba (an heirloom mini-beefsteak) and Green Zebra and they did OK, but the fruit production was not great. And I know I'll plant a few more heirlooms this year as well; just not yet.
The variety I've chosen are Texas Agri-Life Extension-recommended which have proven the test of time for this area: SolarFire and SunPride (6 of each). I've planted these varieties before and have had great success and production from both.
Anyway, potting up tomatoes is simple enough. I use one-gallon pots (used ones work just fine) and fill them with my favorite, premium, pre-moistened potting soil mix, enriched with about 1/2 cup of organic granular fertilizer per plant.
Plant the young, healthy tomato transplants as deep as their first set of leaves into their new temporary homes. Thoroughly water them in with a diluted soluble fertilizer.
The next step is crucial to successfully potting up tomato plants. Find a sunny, sheltered spot where the plants will benefit from light and warmth without being exposed to the wind. I'm fortunate to have a greenhouse to house my tender little transplants, away from the elements.
It still gets very cold here at night. Two nights ago it dropped to 23F! So what I also do is cover my plants with a frost blanket as added protection. The thermometer this morning indicated my greenhouse got down to 43F last night, even with two small greenhouse heaters! That's way too cold for the young plants. It's necessary to provide extra protection if the temperature is expected to dip below 40F--the temperature at which the tomato plant will "harden off". It may not necessarily die, but the plant will chemically shift from growth mode to survival mode and you might as well just throw the plants out and start over again.
It's also important not to let the young plants dry out but they don't like "wet feet" either. Consistent moisture is key. When the tomato plants are in the greenhouse like this, I water them with a water soluble fertilizer every few days...when they feel dry to the touch of my index finger. This way they get all the micronurients they need while in growth mode.
If everything is done properly and with a little good luck, your plants will have a well developed root system, have a strong girth around the plant's main stem and be an aggressively growing little green plant by the time you put them in the ground. But before planting them, it's important to "harden them up" a bit...in other words, gradually get them used to the outside elements. About two weeks before I plan to put my transplants in the garden, I begin putting them outside for increasing lengths of time each day. Begin with about an hour or two, then a few days later, make it a little longer, etc, until the plants are outside most of the day and even overnight if the temperature is warm enough.
Once planted outside, to ensure your potted up tomatoes have optimum fruit production in the garden, make sure they get at least 8-10 hours of intense sunlight, mulch them thoroughly and use drip irrigation. I fertilize my tomatoes every three to four weeks with one cup of organic granular fertilizer, applied away from the stem and over the root system and water it in.
I use the same potting up procedure for young pepper plants as well. This year I've got a head start on Aladin Yellow Peppers and Camelot Sweet Bells (which turn red when ripe...my favorite).
Potting up tomatoes (and peppers) is not necessary or difficult. But it does give you a jump start on fruit production from your summer plants. And I for one, cannot wait for that first bite of a homegrown tomato. Then I know for sure...summer is here!