The basics about growing tomatoes
If you want actually get yummy red tomatoes to eat before winter, there are some things you need to know. It’s not a lot of information and it is not complicated, so don’t be discouraged. Just a little knowledge of factors affecting when tomatoes will ripen will help you a lot. Here is a basic list, but I will explain each item more below:
- determinate versus indeterminate
- days to maturity
- overall health of plant
- when to plant
- macro and micro climate
- watering
- diseases and pests
- vine support and pruning
Determinate versus indeterminate
Determinate and indeterminate has to do with how a tomato plant sets fruit. Determinant varieties tend to set their fruit all at once and then be done. This won’t necessarily all be in the same week, but depending on the variety, it could be. However, my favorite determinate, Heinz, usually continues to produce at least some tomatoes until the end or our relatively short southwestern Idaho summer.
Determinate tomatoes tend to be smaller, more compact vines. The plant stops growing at a certain point so as to get on producing a bunch of tomatoes at once. This can be great if you want to process tomatoes for storage, but is not so great if you want a slow, steady supply of tomatoes over the summer.
On average, determinate tomatoes seem to mature in fewer days than indeterminate tomatoes. However, you probably won’t find very large tomatoes in this category. So, if softball size, juicy sandwich tomatoes are your main goal, you will probably be planting indeterminate tomatoes.
This is NOT the same as hybrid versus non-hybrid. The categorization of hybrid or non-hybrid can be thought of as whether or not the plant will reproduce seed true-to-kind. Non-hybrid plants will produce seed that can be reliably collected, if so desired, to grow the exact same variety of tomato next time. If you don’t want to collect seed or are not concerned about which kind of volunteers sprout next spring, this distinction won’t matter to you.
Days to maturity
If you live somewhere that has real winters, you will want to find out what your average days of last spring frost (SW Idaho, about May 15) and average first fall frost (SW Idaho, about September 15) are. This will tell you how long you can reasonably expect your warm weather crop growing season to be. Tomatoes are a warm weather crop.
A warm weather crop needs warm weather to grow and produce fruit. Cold weather stunts its growth and frost kills it. Keep in mind that there can be very warm spells in the spring and STILL be a late spring frost.
Look on your seed packages or at the plant labels of the nursery plants and find the expected days to produce fruit on your tomato plant. You don’t just want to know when the plant is mature. You want to know when it will give you tomatoes! If it doesn’t have that information, don’t buy it. You have no way of knowing from just looking at the plant whether or not it will get around to growing red tomatoes within your season’s limits.
The average southwestern Idaho warm weather crop growing season is very close to 90 days. If you want very many tomatoes, you will want your plants to be able to produce tomatoes before that. That usually means choosing a variety that will at least start giving tomatoes in early August. That means you will want your tomatoes producing by around 70-75 days after planting.
That really only gives you garden fresh tomatoes for sure for about a month. Even if the first fall frost holds off a bit longer than usual, the weather tends to get cold enough that tomatoes don’t ripen much past the middle of September.
What the plant looks like in the garden nursery
Transplanting can make all the difference in how a plant will continue to grow. And this begins with how it is doing in its original garden nursery pot. You don’t necessarily want the largest plant.
Think about your new tomato plant like it is a child. If you are going to adopt a child and take care of him, will you have a better chance of forming his character and habits if he is older or younger? Exactly. Younger.
Older plants have often spent enough of their life in pots so that it has affected their future growth in unavoidable ways. If they have become root bound (roots filling the pot so much that they are starting to wind tightly around each other), then their growth has been stunted. They might not recover.
If the plants have been growing closely to other plants, they may be tall and spindly in ways that won’t be apparent when they are all still right next to each other. Tall and spindly makes them more prone to wind and water damage. Some unhealthy height can be accommodated by planting the tomatoes deeper than the original soil line. This is not true for all plants, but tomatoes root along the stem quite easily, making this a good solution.
You don’t want there to already be blossoms on the plants either. Blossoms mean that the plant thinks it is done with most of its growing and needs to produce seed for the next generation. If you really want to buy a particular plant that has blossoms already (only ones available of a variety you want or they are on sale), you will want to pluck off the blossoms as soon as possible. This will signal to the plant that it is free to put more energy into growing again. It will transplant better because it is not trying to do so many things at once!
For the record, this is why it is better to buy your flowers before they bloom, too, as the plants will then be more vigorous.
When to transplant
You want to be sure of 2 things before you transplant your tomatoes out into the garden.
- they have been hardened off
- the weather will be reliably warm
Even if a nursery plant has been outside, it might have been under some latticed cover. Such a set up helps nurseries with water and weather issues. If the plant is in direct sunlight when you buy it, you still might want to either check and see how long it has been outside OR just go through a few days of hardening off to make sure.
The earliest I plant my tomatoes out is the beginning of May. I usually only do this if there has been a long enough spell of hot weather that I am having trouble keeping them adequately water. Still, I keep checking the nightly forecast for frost and sometimes cover them every night just to be safe. At least until the latter part of May.
I have not found any significant advantage to planting tomatoes out prior to that. If you have a greenhouse or cold frame set up that might allow you to keep the plants in a particular spot, there might be some advantage. However, it has been my experience that plants that I wait to plant out until it is warm flourish just as well, if not better, than plants I try to force in various ways in the cooler spring weather.
Transplanting is always a bit of a shock that the plant needs to expend some energy recovering from. The more of a shock it is, the longer it will take the plant to get on the path to producing tomatoes. One thing that actually helps the transplant is roughing up the roots a bit so that they are stimulated to grow beyond the original pot. Roots that don’t get that message clearly will tend to stay in the same shape as the original pot and the plant will not be as vigorous.
Where to plant
You want your tomato plants to get as much sun as possible. If they could be exposed to sun from dawn to dusk, that would be optimum. If they can’t you will want to make sure they get as much sun in the middle of the day as possible, at least 8 hours worth.
To make sure this is happening, you will want to go out and note sunlight patterns in the intended growing area. You would be amazed at the shadows that come and go when you aren’t looking. Also, be aware of how other plants will leaf out or grow up around that area. I always plant my tomatoes where they will not be blocked by plants on trellises or tall plants like corn stalks.
How to water your tomatoes
Just like most young plants in the spring, seedling tomatoes will thrive with any watering that mimics spring rains. After that, overhead watering is not optimum for tomatoes. The foliage does not like to be wet for most of its life. Dampness on blossoms or developing fruit creates problems.
The roots of tomatoes like to get pretty dry between waterings, too. These are NOT swamp plants. They like dry heat, with adequate intermittent watering. I use drip irrigation once or twice a week on my maturing tomato plants, depending on exactly how hot it is.
The best way to gauge water needs is to feel the soil near the base of the plant about an inch under the surface. Of course, you want to do this in a way that doesn’t break major roots or dislodge the plant. Remember that the roots tend to mirror the top growth, so pick a spot within the root zone, but not too close to the base of the stem. If the dirt is damp enough to press together, but will still crumble easily, it is probably time to water again. If the soil is bone dry, don’t wait so long next time. If the soil is any wetter than bowl of thick oatmeal, let it dry out more first.
Pests and disease
I have not had a lot of problems with pests of disease in my Idaho garden. My main problems have been little black beetles, which were gone with one spraying of insecticide. And some plants have dies from a leaf curling disease. This condition doesn’t seem to spread, but I still always take the precaution of removing dying plants promptly and cleaning gloves and equipment afterward.
The thing to remember is that when problems occur, they tend to occur quickly. It can be easy to forget to observe your plants when you are just waiting for tomatoes to grow. Examining them every view days for issues can mean the difference between losing one plant or all of them.
How vine growth and pruning can affect tomato production
Indeterminate tomato plants are usually vines in the truest sense. They grow and spread in unwieldy ways that can make plant maintenance or harvesting difficult.
On one hand, the leaves can help protect the growing fruit from sun scald. On the other hand, a bit of pruning allows the plant to put more energy into fruit production. For these reasons, it can be helpful to use a cage or stake to guide and support your tomato plants. This makes it easier to see the tomatoes and keeps it off of the ground where pill bugs and water will ruin it.
Some people say to prune the suckers from tomato plants. These are defined as the branches that grow in the notch of another branch. Supposedly they do not produce tomatoes, but I haven’t found this to be strictly true. What I have found to be true is that pruning back the plants some seems to direct its energy into more tomato production.
Another twist on this is that you can get the larger and partially red tomatoes to ripen faster toward the end of the season if you pick off blossoms and prune back the plants. This is most useful for indeterminate tomatoes, which will keep trying to take over the world as long as the weather allows.
Varieties of tomato I have grown successfully in Southwest Idaho
Keep in mind that every year, I have gardening disappointments. Sometimes I know why and other times I have no idea why. Sometimes I learn important things, but other times I do things exactly the same (as far as I can tell) the next year and have excellent results. I blame it on the moon and weather patterns!
Even with that, there are some tomato varieties that have been very reliable. I grow these from seed, which if you haven’t tried it, is not rocket science. It just takes some diligence and patience.
That doesn’t mean I won’t try new varieties. I almost certainly will. Still, it is nice to have a few old faithfuls.