Ask a Master Gardener

Photo of a cherry tomato on the vine

Growing Tomatoes

4/2/24

Hands down, the most popular vegetable (technically a fruit) for urban gardeners has to be the tomato. One of the primary reasons is that home grown tomatoes just taste so much better than store bought tomatoes. No disrespect meant to grocery stores. It’s just next to impossible to pick, transport across the country, and sell a tomato that tastes as good as one freshly plucked from the vine. But to get that home-grown tomato taste, you’re probably going to want to grow your own. So, let’s talk about growing your own tomatoes.

Tomatoes plants can be started from seed indoors but it’s a little late to start those seeds and expect to get them in the ground around our average final freeze date of April 15th. At this point, you are probably looking at purchasing plants from one of our local vendors. When shopping for tomato plants, and then caring for these plants, there are a few things you should keep in mind.

The first question you will need to ask yourself is do you want a burst of tomatoes all at once, or do you want to enjoy tomatoes throughout the growing season? The reason we ask this question is that there are two types of tomato plants: determinate and indeterminate. Determinate tomato plants produce a single crop, all at once. A Roma tomato is a good example of a determinate tomato. Determinate tomatoes are great if you are wanting to can tomatoes of perhaps make a big batch of salsa or pasta sauce.

Indeterminate tomatoes produce tomatoes all season long. I tend to lean toward indeterminate plants. Probably because I’ve never really figured out the whole canning thing.

Determinate tomatoes tend to be bushy and do well in those cone shaped tomato cages we are familiar with. Indeterminate tomatoes are more viney and will likely need a larger, more substantial support system.

In reality, I guess you don’t have to pick between the two, you could grow both. But it seems that most growers lean more toward one type than another.

Next, you’ll need to decide between heirloom or hybrid tomatoes. Heirloom tomatoes are the ones whose seeds have been passed from one generation to the next with their seeds growing to produce the same type of tomato. If you plan on saving seeds for next year, you should look into heirloom tomatoes.

One thing to remember is that hybrids are not GMOs. GMOs are plants that have been genetically modified in some way. Hybridization of plants occurs naturally through cross pollination. These hybrid tomato plants have just been cross-pollinated to perhaps create plants that produce more fruit or have greater disease resistance.

I mentioned that if you plan on saving seeds for next year, heirlooms are the way to go. This is because the seeds from hybrid plants might not produce the same type of tomato you were expecting, they might revert back to one or the other of the two cross pollinated plants.

Now you’ll need to decide how many tomato plants you’ll need to plant to satisfy your tomato cravings. The general rule is about 3 to 5 plants per person if you are wanting fresh fruit all season. If you are wanting to can your tomatoes, think more like 5 to 10 tomato plants per person. In reality, it just depends on how many tomatoes you want.

Next up is determining the space between your tomato plants. When you purchase those small little tomato transplants, it’s easy to think you can plant them fairly close together, but your tomatoes should be spaced about 2 to 3 feet apart. To be sure, look at the spacing requirements on your particular plant, but three feet apart is a good rule of thumb. Overcrowding can be a contributing factor to increased disease development on your plants, so it’s always a good idea to give your plants some breathing room.

Tomatoes also do best in a location where they receive what is called “full sun.” Full sun is considered 8 to 10 hours of direct sunlight each day. If you don’t have a location that receives that amount of sun, you can still grow tomatoes, you just won’t have those nice robust plants or the amount of production you would have had if they had gotten enough sun to meet their needs. A little shade in the late afternoon isn’t a bad idea, but not a requirement. I know the tomatoes at our Seed to Supper Farm get sun from sunup to sundown and they do great without that afternoon shade, but that’s not always the case.

Tomatoes will do best when provided with some additional fertilizer. To start with, you can sprinkle them with about a tablespoon of 10-20-10 when planting. When the first fruits are about 1/3 grown, add another two tablespoons per plant. Then add another two tablespoons after the first fruits ripen and then again about a month later. Be sure to water in the fertilizer if we don’t get a good rain.

Some people refer to tomato plants as “heavy drinkers.” All this means is that they like their water and do best when watered appropriately. Tomatoes tend to let you know when they are thirsty. Keeping them properly hydrated will also help protect them against disease because healthy plants do better than stressed plants when exposed to some sort of plant disease.

Now if you are thinking you don’t have a place to grow tomatoes in your yard, tomatoes actually do really well in a container like one of those utility buckets that are available from one of the larger home improvement stores. Just be sure to drill holes in the bottom to allow for drainage.

Now that you’re all set to grow your tomatoes, I’ll see you in the garden.

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: OSU Ag.Comm.