Now that it's definitely becoming more spring or even summer-like, I've started thinking about growing a few tomatoes. Because I love them. I am, however, a notorious tomato snob. And who could blame me? These vegetables, which are indeed fruits, can be absolute ambrosia, when they're sweet, and smooth; succulent and tangy. But, when they come from a supermarket, well, you know what they taste like. Grainy, dry, flavorless. Sometimes even white on the inside! That's so ghastly! Fortunately, we can grow our own, even here in Southern Nevada, or maybe just encourage other people to grow their own, which they will want to share with us.
Tomatoes grow best when they get lots of sun, not too much heat, ample water, and rich soil. They'll do fine in pots or in a garden, but they aren't completely fool proof. They can develop a number of disorders that might break your heart. These can be particular problems here in the desert, and I thought that today, I'd talk a little about dealing with some of these problems.
Sometimes flowers will appear on the plant, but they don't result in tomato fruits. The flowers actually drop off. How's that for a disappointment? Unfortunately, there's more than one reason why such an awful thing can happen.
For instance, if the plant produces flowers, but the temperature then goes much above 90°, or much below 55°, well then the plant is stressed, and it's stressed to such an extent that it can't support flowers, much less fruit.
Another possible cause is incorrect watering. If a plant is watered too little, of course it won't be able to maintain flowers or fruit. But just as devastating is too much water. If the tomato plant is in heavy clay soil with poor drainage, then the roots drown and don't perform their necessary functions and, as a result, the plant can't maintain flowers.
Too much fertilizer, or fertilizer applied when the plant's producing a mass of flowers, can cause blossom drop. I don't like to anthropomorphize plants, but when fertilizer isn't timed right, it's as if the plant gets confused, and thinks it's supposed to go back to making lots of leaves. This messes up the flowering. The best time to apply fertilizer, particularly nitrogen, is usually early in the season, when leaf production is just getting rolling.
Occasionally, even the most intrepid and dutiful gardener may discover that the bottom of a tomato has become hard, black, and really unappealing, but the rest of the tomato looks OK. This is an actual condition called 'blossom end rot'. It shows up when the fruit is quite young, and the tomato will even continue to grow a bit after the discoloration begins to show up. You usually see it when the temperatures are fairly high.
I find it really interesting, in a tragic sort of way. What happened was - a lack of the element calcium getting to the fruit back when it was just a tiny swelling at the base of the flower. Without enough calcium, cells, which were dividing at the time, didn't grow properly. But don't be fooled. It's not that there was insufficient calcium in the soil. Here in the Mojave, we generally have tons of calcium - you've heard of caliche. But it doesn't do any good unless it gets to the developing cells. the problem was that the very young fruit didn't get enough water at a critical time. Water carries the calcium to the rapidly growing tissue.
By the time you see the problem, it's too late to do help the individual fruit that's been affected. If you find blossom end rot on a tomato or other fruiting vegetable for that matter, remove the fruit, and address the problem. Like so many other things, the way to solve the trouble is to prevent it. Make sure that a tomato (or pepper or cucumber for that matter) plant is kept regularly moist (not wet, since that'll cause another set of problems), especially when there are flowers present.
Another sad event is when the beautiful tomato you've nurtured, and protected, and watched grow, develops unsightly cracks. These can be either concentric, or radial, like the spokes of a wheel. Again, the answer to this problem is mostly proper watering. If the fruit of a tomato is allowed to become too dry, and then overwatered, its skin actually cracks. It can happen with any variety, but some are more susceptible than others, so check to see if there's any information on cracking before you buy seeds or seedlings.
If you keep tomato plants moist (not wet) and well nourished, then you've lowered the likelihood of disappointment in your vegetable garden.
For KNPR's Desert Bloom, this is Dr. Angela O'Callaghan of the University of Nevada Cooperative Extension. Enjoy your delicious tomatoes!