Growing Heirloom Tomatoes in a Short Growing Season

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It's been a very unusual year for tomatoes here in the northwest Texas. Hardly any of my tomatoes ripened after sitting for months on the vine still green. Other gardeners in my area have experienced the same thing with their tomatoes, which is strange.

Growing heirloom tomatoes or indeterminate tomatoes in an extreme climate can be more difficult because tomatoes typically take a long time to produce. Heirloom tomatoes are different than hybrid or determinate tomatoes in that they grow much larger and put out fruit slowly over a long season.

But I know many of you are like me and want heirloom tomatoes! (even if it's a little more work). In my area, it is too hot for tomatoes to fruit (months of 95+ degrees) during the summer but we also get freezes from Halloween through Easter. There's only 1.5-2 months in the spring and in the fall where the weather is actually temperament.

This can present a real challenge for growing tomatoes.

How To Start Heirloom Tomatoes From Seed

Timing

If you want to grow heirloom tomatoes in a short growing season, you will have to start tomatoes from seed at the right time. It takes about five months from when you start your seeds until you will be picking ripe tomatoes.

You will want to make sure that when the tomatoes are setting fruit that temperatures are in the "sweet spot". Ideally this is between 50-85 degrees but I have had tomatoes setting fruit when the temperature is in the 40s and up to about 90 degrees.

Heirloom tomatoes will start to hit that flowering stage around month 3 and will keep going as long as the weather permits. To get a decent size harvest, you'll want to have enough plants and at least 2-3 months of those "sweet spot" temperatures.

Take this into consideration when you are planning to start seeds.

Heirloom tomato timeline (times are approximate):

• Weeks 0-6/8: Start seeds
• Weeks 6-8: Transplant the plants into the garden and watch them grow
• Weeks 10-13 (aprox.): Plants will begin flowering and setting fruit. Temperatures should start to enter the "sweet spot" around week 12.
• Weeks 20-24 (aprox.): You should start to get ripe tomatoes by this point. It's okay if temperatures are starting to get too cold or hot around this point but you will want to make sure to take measures to protect the plants from either freezing or getting sunburned.

Starting seeds

I prefer to start most of my seeds including tomatoes right in 4 inch pots filled with potting soil. I often mix in a tiny pinch of bone meal and blood meal and sometimes, a couple pinches of worm castings. In the past, I've had tomatoes starts die on me from lack of nutrients because they are heavy feeders. I don't typically use seed starting mix because I find I don't need it for most plants including tomatoes.

After four weeks, they will be ready to transplant into half gallon containers.

Around weeks 5-7 you will want to begin hardening off your seedlings for 1-2 weeks before transplanting them into the garden around weeks 6-8. When I transplant the tomatoes into the garden, I add another good size pinch or two of blood meal and bone meal as well as mycorrhizae into each hole. Another good option for tomatoes is tomato tone. I mulch around the plants with straw. I personally can fit 18 plants into a 8 ft by 4 ft bed using the lower and lean method described below.

The Lower and Lean Method for Growing Heirloom Tomatoes

This is personally my favorite way to grow heirloom tomatoes. It allows me to fit more tomatoes in a small space and prevents my tall, indeterminate tomatoes from outgrowing their trellis or cage (they can get 7-10 ft tall!). It also supports indeterminate tomatoes better than a cage does.

Indeterminate tomatoes (which includes most heirloom tomatoes) grow more like a tree whereas the determinate (typically the hybrid tomatoes) grow more like a bush. So the heirloom tomatoes do better when grown along a single support like a stake or string.

Before planting your tomatoes, make sure to have an overhead structure in place. The most sturdy way to do this is to build a structure that has a strong overhead bar that is at least 6 ft or so above the ground. You should almost be able to do a pull up on it without it bending too much. Electrical conduit would be a good material for this.

I personally am not very handy so I use 7 ft bamboo poles that are tied together almost like a teepee. It isn't the most sturdy, so I secure it to my outer structure which I discuss below.

When I go to plant, I fasten a zip tie to the overhead bar, hook a tomahook onto the zip tie and loosen the string until it reaches the plant. I then clip the plant onto the string, and prune leaves touching the ground.

As the plant grows, continue to clip the main stem onto the string about every 9-12 inches or so. Once it reaches the top, loosen the string and lower the plant onto the ground. It should gently curve at the bottom.

Pruning

Pruning is an important part of the lower and lean method. Number one, make sure not to over prune the plant because it needs some leaves to grow and produce fruit.

Remove lower leaves on the plant that are close to the ground. This will reduce disease. As the plant grows and you lean it onto the ground, make sure to remove those bottom leaves.

Also make sure to prune suckers and any leaves that look sick or dying. The main goal is to train the plant to grow as one main stem like a tree. Naturally, the plant will try to branch off, but you don't want to let them do that or you will end up with a chaotic tomato jungle!

Protecting Tomatoes from Cold Weather

In order to grow heirloom tomatoes, I have to grow them in either the fall or early spring. This means that there will be some nights where the temperature drops below freezing (which will be the end of my tomato plants unless I protect them). Ideally, I like to keep the plants above 40 degrees.

To get around this, I build a small house for my tomato plants (I call it the tomato paradise). You could build something like this with pvc or conduit pipe but I personally have found it easier to use a crop cage. I have a 8ftx4ft cage that sits directly on top of my metal 8ftx4ft raised bed and is fastened to the raised bed with ropes (there are small holes in the corners of the bed that I poke the rope through). It comes with a net that holds that whole frame in place.

This cover keeps out birds and squirrels, and I pollinate my tomato flowers using an electric toothbrush every day/every other day. When it's hot, I clamp shade cloth over the top and when it's cold I wrap the entire thing in frost cloth/sheets.

I have a small heater fan inside of the structure that I turn on when its below 40 degrees.

A heated greenhouse would also do the same thing but I do not have the resources or space to build one in my small backyard. Some people might find this to be too much work but I personally really want heirloom tomatoes! Also, this rest of my fall crops are low maintenance so I can devote more attention to the tomatoes.

This is how I manage to grow heirloom tomatoes despite extreme heat and cold. If you have any questions, be sure to comment down below!