How To Grow Tomatoes in Oklahoma
Selecting a tomato variety
There are some varieties that do much better in the heat. There are some tomato varieties that produce a lot more fruit than others. Nevertheless, almost any variety is suitable for growing in Oklahoma.
There are some exceptions to that rule, though.
Oxheart-type tomatoes, in the heat of Oklahoma, tend not to produce much fruit.
For those tomato varieties that produce oversized fruit – varieties such as Omar’s Lebanese and Big Rainbow – they don’t tend to do well in Oklahoma either.
Heirlooms, on the whole, do well in the heat of Oklahoma. They may not look as pretty as hybrid tomatoes. But this is because their breeding does not include the ‘pretty look’. So, often heirloom tomatoes will be cracked, catfacing (scarring and cavities near blossom end), with zippered marking over the skin. Oftentimes, heirloom tomato fruit is oddly shaped too.
Notwithstanding, mostly, heirlooms have a better flavor than hybrid tomatoes.
Selecting a tomato type
When you choose tomato plants for your garden they can be determinate, indeterminate, semi-determinate, or dwarf.
Read: What is a determinate tomato variety? What is an indeterminate tomato variety?
Indeterminate tomato varieties generally produce fruit throughout the entire summer. Even when the fruit is setting and ripening, indeterminate plants continually grow wider and taller. Some indeterminate tomato plants reach 10 feet, some even higher than that.
Determinate tomato varieties generally only grow to around 4 feet in height, but often they are only around 2 feet tall. Determinate tomatoes produce a full crop in a short space of time. After setting fruit, they don’t grow much more, if at all.
Semi-determinate tomato varieties are dwarf-like. As such they are much better suited to patio growing or at least to the small garden when container growing is a necessity.
Growing for disease resistance
Irrespective of where you are in the world, diseases can be a problem for tomato plants. There are no tomato varieties that are completely disease resistant.
The disease-resistant tomatoes – the ones that have been proven to offer disease resistance – will demonstrate that resistance by way of some letters which are added to their name.
Among the most common of these are fusarium wilt (F), verticillium wilt (V), Alternaria (A), tomato mosaic virus (T), and resistance to nematodes (N).
The whole concept is further complicated because there are different disease races. As an example, the Big Beef tomato is often seen written like this: Big Beef VFFNTA. This means it is resistant to verticillium wilt, as well as two different fusarium wilt species, resistant to nematodes, tomato mosaic virus, and also to Alternaria.
Just because you see a tomato that has no letters following on from the name doesn’t necessarily mean it offers no disease resistance. What this means is that it may not have been tested officially and it may not be officially proven to offer disease resistance.
Frequently, you’ll find that heirloom tomatoes have no disease-resistance designation. That’s because heirloom tomatoes have been around for at least 50 years. And because of that, no one company owns breeding rights. So no one company is willing to invest money in having them officially tested.
That’s not to say that heirloom tomatoes do not have disease resistance. Many heirlooms offer good disease resistance.
Color of fruit
The ideal tomato fruit, in accordance with the interests of mainstream agriculture, is red in color. It is globe-shaped as well.
Tomatoes, though, are available in a variety of colors.
Over the previous ten years or so, heirloom tomatoes that are available in various colors have become very popular among home tomato growers.
You can buy tomato transplants (seedlings) and seeds of tomatoes that are described as red, yellow, orange, pink, purple, black, white, and bi- and tri-colored.
Tomato color descriptions aren’t always exact. For example, many of the so-called purple tomatoes are more of a dark red.
What do tomato ‘seasons’ mean?
Early season; midseason; late-season; all-season. What does it all mean?
Let’s say you bought transplant tomato seedlings. You’ll enjoy a first fruit harvest within a certain number of days after the transplants are, well… transplanted into your garden. That’s what is referred to as DTM – days to maturity.
Early Girl, which as the name suggests is an early-season tomato, will provide you with fruit within about 52 days after transplanting.
Mid-season tomatoes such as Celebrity will provide you with a first harvest in around 70 days from transplanting.
Late-season tomatoes, like Brandywine for example, and you can harvest around 90 days from transplanting.
For Oklahoma, early- and mid-season tomato plants have a tendency for producing more fruit than late-season tomato plant varieties.
Again, in Oklahoma, because the mid-summer months are so hot, the general rule is that tomato plants don’t produce much fruit at that time. Some varieties, regardless of the heat, do well, though.
And again, as a general rule, you’ll find that the varieties that grow smaller-sized fruit have a tendency for producing throughout the summer months.
As such, if you want a summer-producer, go for grape, cherry, and currant type tomatoes.
To get around this issue, some people like to set out new tomato plants starting from June or July. This will provide fruit during the fall.
Tomato varieties that do well in hot climates
With high temperatures, you’ll find that tomato production is impeded.
There are some tomato varieties that have been bred to do well in hot climatic conditions.
Nevertheless, the downside of these particular tomatoes is that they don’t generally have the best flavor.
As the saying goes, “You can’t always have your cake and eat it.”
Here are a few tomato varieties that do well in hot conditions:
Some tomato varieties do well in terms of keeping well for a long time. You can pick these fruits when they are still green or when they are just starting to turn red.
These ‘long-keepers’ can be stored in a cool, dry room. They can then be eaten long after the fall frosts have knocked out all other tomatoes.
Among these long-keepers are:
Old-Fashioned Garden Peach
Yellow Out – Red In
Best soil for tomatoes
Tomatoes do best in soil that is of a sandy loam type. Well-draining soil. A soil that is rich in terms of organic matter content.
If soil is overly sandy, it is heavy in clay, or if it is silty, it’s easy to improve. Add in a large amount of organic matter.
What organic matter is best? Any, really:
hardwood or bark that is finely shredded
soft rock phosphate
dry grass clippings
straw stable bedding (compost it if it is still relatively fresh)
partially decomposed hay
Don’t add too much material that is rich in nitrogen. Composted manure is high in nitrogen so don’t add too much of that. If your compost is too high in nitrogen you’ll get plenty of foliage but not a lot of fruit.
The general rule is to add up to 1 pound of composted manure per square foot.
How about if you have a slow-draining soil?
Raised tomato beds are the answer here. Raise the beds to between 4 and 10 inches above the normal soil level by mounding up the soil.
Soil pH is an important factor as well. If you have a soil pH that is below 6.0 (very acidic) add lime or limestone to raise it. Adding dolomitic limestone is also good. This will add to the magnesium content in the soil. And because tomatoes need magnesium and because magnesium is frequently lacking in soils that are acidic, adding dolomitic limestone is definitely a good thing.
How to feed tomatoes in Oklahoma
If you’re an old-school organic-type gardener, it’s more than likely you’ll have the understanding that by adding various amendments to your soil you’ll not have to rely so much on chemical fertilizers.
It’s a matter of, if you feed the soil, the soil feeds the plant.
Each year, though, some soil nutrients need to be replenished.
Add organic amendments, top dress, add organic fertilizers. All of these can be taken care of before planting your tomatoes.
Amending your soil the one time will not be enough. This is an ongoing process.
Adding some organic tomato fertilizers to the hole when you are planting your transplant tomatoes is good practice. You can also top-dress with an organic fertilizer throughout the growing season. You may have your own preference for organic tomato fertilizer. If not, try Tomato-Tone.
The general rule for tomato fertilizers in terms of the main nutrient ratio is 1-2-1, which is the same as 10-20-10, or 12-24-12. The numbers apply to the key nutrients – N-P-K or nitrogen, phosphorus, potassium.
Other organic fertilizers you may wish to try with your tomatoes are water-soluble. Liquid seaweed, Garrett Juice, Alaska liquid fish fertilizer, or a chemical-based one such as Miracle-Gro’s Tomato Fertilizer.
When to plant tomatoes in Oklahoma
If you wish to cover over your tomato plants in the event that they need protection when there’s frost then, by all means, you can plant early in the season.
Personally, I wouldn’t do that because it’s a lot more work.
The weather in Oklahoma is particularly variable. It’s not so uncommon to experience frost in late April, even early May.
So, best to find out when the typical date is for the final frost in early spring for your county.
Once the threat of frost has vanished it’s time to transplant your tomato transplants into your yard.
Aim to plant early in the season, being very mindful that you do want to avoid any late frosts.
Why worry about early planting?
It’s because tomato plants provide maximum yields only if they bloom prior to daytime temperatures rising above 92 degrees F.
What’s more, your tomato plants must bloom and must set fruit prior to nighttime temperatures rising above 75 degrees F.
This means that depending, of course, on where in Oklahoma you reside, there’s a relatively short ideal timeframe for blossoming and fruit set.
If you were to plant your tomatoes out late, like in mid-May or perhaps even later than that, if your plants were already large that’s fine. If your plants were small you’ll likely not get many blooms and thus you’ll likely get few fruits. That is not until mid-summer. But by that time the temperature is going to be too high for a decent fruit set.
Moving on: should you have established your transplants under grow lights, if these transplants are planted out in full sunshine and exposed to early springtime winds which can be harsh, your transplants will likely perish.
To harden them off adequately, you’re looking at at least a week. So, that in mind, start these transplants out with an hour or two exposure to outside conditions each day. Increase this by one hour each day until your transplants are ready to handle the tougher conditions.
When you’re buying transplant tomatoes look for transplants that are between 5 and 12 inches in height. These should have a healthy appearance. Don’t go for the ones that have woodiness in the stem. These will be too old.
Any transplant that is more than 12 inches in height can still work fine. But with a larger plant, there’s more possibility for transplant shock.
Dig the holes for your transplants deep and wide. Mix in some fertilizer if you prefer, as noted above.
With tomato plants, they will form new roots at any part of the stem that is in the soil. This means because you want a strong root system, set your plants nice and deep. Don’t bury any leaves. Pluck off the lowest pair of leaves and plant your transplants into the soil to that height.
Make sure the transplants are firmly positioned in the soil. Then water well.
Your transplants ought to be positioned no closer than 30 inches from one another.
If your tomatoes are indeterminate it’s best to plant them between 3 and 4 feet apart.
If you plant too close the fruit yield will be lower. Plus, that can improve the chances of foliar disease since there’s reduced airflow between plants.
If you have the tendency for planting too many tomato plants, by all means, reduce the spacing. Rules are sometimes to be broken.
Additional tomato care
If your plants need staking, and most do, don’t wait until your tomatoes have been in the ground for weeks. Position your stakes right away so as to avoid root damage.
If you want to add cages, do that now too. Adding cages later can cause damage to the foliage – the branches.
Be sure to label your plants if you have a variety of different varieties. Tie each label to the stake. To make sure the labels don’t ‘vanish’ wrap them with duct tape around top and bottom.
If you want to companion plant your tomatoes, which is good policy as there is an assortment of benefits to be had with companion planting, now is the time.
Companion planting can help to deter some pests, it can help to improve the growth of tomato plants, and it can help to improve fruit flavor.
As the plants begin to grow you can add some mulch to the soil surface around the stem of each plant in turn. Mulch helps to reduce weed growth and it also helps to retain soil moisture. Plus, mulch can look real pretty, depending on what you’re using to mulch. Chipped bark, for example, is very aesthetically appealing.