My dad and I have email conversations about various garden topics all the time, and a recent one seemed to be full of a lot of good advice on the subject of tomatoes. I’ve taken a couple of his emails and combined them for posting here.
Tomatoes are the most planted garden vegetable (fruit). In Texas, it is important to plant them at the precise time the calendar says they should be planted. They must be big, strong and blooming before the very hot temperatures hit in June or they will not bear fruit. The grower’s job is to find the biggest, most healthy plants to plop in the ground as soon as hard frost warnings are over. Be prepared to cover them if a light frost comes along. After that, pour on the organic fertilizer and water to get them to grow as fast as possible. Seldom will the plants set many tomatoes after the first of June as it is too hot. So, we sit and wait watching every day to make sure some critter does not run off with or eat our prizes.
Every tomato plant starts declining as soon as the high heat arrives. Concentrate on protecting and harvesting what the plant sets. If a few leaves at the bottom start to die back, cut them off with a scissors or your finger nail and put them in the trash—not the compost. The plant will last and put on some new leaves and branches while it is setting fruit. After the last tomato has been harvested you might as well pull the whole thing out and put it in the trash, too. I have tried to save tomato plants through the summer and have never been successful. There may be sprays and all sorts of things to try to hold down the viruses and fungi, but if you want Fall tomatoes, a new plant is the best and cheapest solution. Tomatoes are very sensitive to not getting enough water, a so a plant grown in a container might suffer if the container is not big enough.
Fall tomatoes: In my estimation they are harder than Spring tomatoes. Again, the timing has to be just right. The nursery business does not cooperate. They usually do not have the plants until it is really too late to plant them. Proper time is about July 15th to July 31st. The problem then is daylight conditions decrease dramatically by mid September when the first cool front thinks of coming though which will allow the tomatoes to set fruit. Most tomatoes will not set unless the temperature at night is below 70 degrees. Small-fruit varieties and cherry tomatoes will sometimes set above that level. So, if they set around the middle to end of September, you then have to get the tomatoes to grow up and begin ripening before frost. With the shorter days and cooler nights, it is tough to get large tomatoes to ripen. Compared to Spring it is like slow motion. So, a smaller variety is better. Unless you start plants from seeds about the beginning of June—which for some reason I never do–you are at the mercy of what you find in the garden centers. I have had some success with Cherry, Donna, and Juliet. For a larger one, I usually try the Early Girl/Boy or Celebrity. I did have some test plants from the Extension Service one year called a 444, I think. It is a tennis ball sized tomato. It did well, but I have never seen it in a garden center. Of course the other challenge is tending and keeping the plants healthy and properly irrigated during the hot days of July and August. Sometimes they require a bit of improvised shade over them during the hottest part of the day at least until they get established.
One could say my dad has had a lifetime of experience in gardening, and these days helps a Houston-area public school maintain organic vegetable gardens he and the school established for the students to have some experience with growing food.