When to Plant Tomatoes in Missouri?
When to plant tomatoes in Missouri? The rules here apply to all tomato varieties and cultivars – Beefmaster tomato, Oxheart tomato, Black Russian tomato, Dixie Red tomato, Stupice tomato, you name it…
Plant your tomatoes (outside) once the air temperatures have climbed a bit in springtime and once the soil temperatures are on the rise from 60 degrees F. Don’t plant when the soil temperature is below 60 F or when there’s a chance of frost.
If the soil temperature is still lower than 50 degrees F it will impair the growth of your tomato plants.
In the southern part of the state, you should be looking at planting your tomatoes outside at any time between April 20 and May 15.
In northern Missouri in addition to the Ozarks, it’s typically advisable to plant tomatoes outside in May – from May 10 through May 20.
In central Missouri, and you’re looking at planting tomatoes outside from May 5 through May 20.
You can plant outside a bit earlier than the given dates if you’re happy to provide your tomato plants with protection.
The following table provides the approximate dates of last and first frosts for various cities in Missouri. Note that the dates provide a probability of 30 percent. Frost dates are averaged from 30 years of data (1981-2010).
When to Plant Tomatoes in Missouri – Last and First Frost Dates in Missouri
Tap the chart to enlarge
Obviously, prior to planting, you’ll want to remove any pots other than peat-based pots which can be dug into the soil along with the roots. Yes, the roots will penetrate peat-based pots. If you do plant peat-based pots ensure that they are planted deeply and not showing above the soil surface level. This is required to avoid the pots drying out. If they dry they attract water away from the root zone.
Tomato plant stems can be planted into the soil. Might seem a bit crazy to do that – a bit counterintuitive. You can’t do that with any vegetables. If you tried you’d have a dead plant and zero crops to show for it.
However, the stems of tomato plants grow roots when planted deeply. You might wish to remove the lowest leaves on your plants. After which plant nice and deeply to encourage a larger root system. Don’t plant any leaves since the leaves will rot and that can cause disease.
Using a soluble fertilizer that has a high phosphorus content (phosphorus is required for healthy root growth), add one cup of fertilizer solution to each individual planting hole. A fertilizer with an N-P-K (nitrogen-phosphorus-potassium) ratio of something like 15-30-15 is ideal. To one gallon of water add 2 level tablespoons of fertilizer. Either that or follow the manufacturer’s instructions.
If cutworms are a problem in your garden, and cutworms are generally an issue for tomato plants in Missouri, you can use a wax paper collar to guard the base of each tomato plant. The collar should be one inch below the soil surface level and two inches above.
Tomato Planting Distances
To enjoy the benefits that healthy tomato plants offer (not least of which is plenty of delicious fruit!) you’ll want to space your plants adequately and provide them with some kind of support as well.
Planting distances are dependent on your tomato plants (determinate (non-vigorous) or indeterminate (vigorous growing habit)).
Read: What’s the difference between determinate and indeterminate tomatoes?
Generally, though, a good distance apart for tomato plants is around 24 to 36 inches apart within each row. If you’re growing very vigorous plants then space them at around 36 inches.
Space each row at approximately four or five feet distant to one another.
What Fertiliser is Best for Tomatoes?
Tomatoes benefit from being fed once every week to two weeks.
A fertilizer that has a high nitrogen content is best to begin with. That’s because nitrogen (N) is essential for the growth of healthy foliage.
One that I use is Osmocote Smart Release. It has a macronutrient (NPK) ratio of 15-9-12. Additionally, it comes with nine other micronutrients.
Osmocote Smart-Release Plus Fertilizer (with 12 nutrients)
At or around mid-season and your tomatoes will benefit much more from a fertilizer that is high in potassium (K) and low in nitrogen (N). Potassium is essential for healthy fruit growth. I like the Miracle-Gro Tomato Fertilizer with its 18-18-21 N-P-K ratio.
Some folks prefer to provide their tomato plants with zero nitrogen at this stage. I like to continue with some nitrogen as it helps to maintain a healthy-looking plant.
Staking Tomato Plants
Properly supported tomato plants will improve overall fruit yield as well as quality. Further, good support makes it easier to harvest.
Plants that are supported are less likely to succumb to disease than plants that remain unsupported.
If you wish to stake your plants you can either make your own or buy proprietary tomato plant stakes from your local hardware store or garden center. You can use soft string to tie your plants to each stake. Be sure to leave a little space when tying so the stem has space enough to expand as it grows. Either use soft string or lever-loop gripper clips are an excellent alternative.
Lever-Loop Gripper Clips for Supporting and Straightening Tomato Plants
You have the option to cage your tomato plants rather than staking. This provides more support. Plus, there’s no need for tying when you use a cage system. A good caging system is Growneer 3-pack Cages.
