Growing tomatoes is one of the most popular vegetables grown in any garden and it’s easy to see why. Nothing tastes as good as a tomato fresh from the garden!
For a successful tomato season, we asked our NGB breeder members to answer 15 of the most often asked growing tomatoes questions we receive. We hope that these answers will help you have a delicious and productive tomato season as well.
Top 15 Questions About Growing Tomatoes Answered…
1. What’s the difference between indeterminate and determinate tomatoes?
Basically, an indeterminate tomato will continue to grow vegetatively (leaves and stems) all season long, and they will also flower and produce fruit all season long. Indeterminate tomatoes typically perform best when grown in the ground rather than a container, and can get quite large/tall. Determinate tomatoes, on the other hand, will grow vegetatively to a certain point and then produce a flush of flowers, which then form fruits. Most determinate tomatoes tend to have a bush habit and can grow well in a container or in the ground. They also tend to produce a large amount of fruit over a relatively short time period (approximately 3-5 weeks depending on variety and growing conditions).
There is a third type called semi-determinate which is bushy, like a determinate, but will set and ripen fruit over a longer period of time. The 2020 AAS Award Winner ‘Celano’ is a semi-determinate. The best way to grow determinate or semi-determinate plants is to place a cage around the tomato while still small and not prune.
2. Can your tomatoes survive if you planted them too early in the season?
They might survive if you keep the young plants warm with a cloche or other protective cover. Tomatoes are not frost-hardy and will die if exposed to 32 degrees F without protection. It depends on what sort of temps you are experiencing. Tomatoes can tolerate the 40s and even high 30s F but don’t necessarily “enjoy” being grown in those temps.
3. If I have started my tomatoes from seed indoors, do I need to gradually prepare them for outdoor temperatures?
It is important to harden off any tender plants before placing them in the garden by exposing them gradually to the harsh outdoor conditions. Put young plants outside where they will receive morning sun but be protected from wind, and move them inside at night. Continue this for about a week, and then begin to leave them outside on nights when the temperature does not drop below 50 degrees F. After a week or two, the plants should be ready to transplant.
4. How do I plant my tomatoes properly?
Remove the lower leaves off of the stem and bury the stem about 2/3rds deep. The portion of the stem that is buried will form roots, which will allow more water and nutrient uptake, making the plant stronger and sturdier. Tomatoes are one of the easiest garden plants to grow. They need as much direct sunlight as possible to produce the highest yield. Native to the tropics, tomatoes require warm temperatures for good growth, so wait until the nighttime air has warmed to about 55 degrees F before transplanting them. Planting tomatoes too soon will only slow them down.
5. How often should I water my tomato plants?
Continue watering regularly for about two weeks until the plants are established. Throughout the growing season remember to water the plants deeply during dry periods for as long as they are setting fruit. Established tomato plants need at least one inch of precipitation per week.
6. I live in the middle of Florida. Everything burns up. The sun is hot during the days. What variety will handle the heat?
There are several varieties that are touted to perform well in the heat but another option is to plant early and choose an early maturing variety that will get ripe fruit before the summer heat. Often times, tomato growers in Florida will plant in late winter for a spring harvest.
7. I’d prefer not to cage my tomatoes, is there another way to support my plant?
There are lots of different ways to support your tomato. The first thing to check is whether the variety is determinate (more bush-type) or indeterminate (more of a vining, larger plant). If you get a thick stake and put it in the ground near the base of the tomato stem, you could tie up the plant along the stake as it continues to grow. Using fencing to support the plant is another option but there are also lots of attractive supports available from retailers. Another option is called the Florida Weave and works well if you are growing a number of tomato plants in a row.
8. Is there any way to prevent blossom end rot on the first tomatoes that produce? Is there one variety over another that is better preventing that?
Blossom end rot on tomatoes typically occurs when there is uneven watering, which oftentimes is out of our control depending on the amount of precipitation. My recommendation is to evenly water as best as you can. Roma tomatoes tend to show the most amount of blossom end rot and cherry tomatoes tend to show the least amount.
9. Should I fertilize during the growing season or just at the beginning?
Tomatoes need phosphorus, nitrogen, potash, and minor elements. Starting your plants off with an ample shovelful or two of compost will go a long way toward making sure the soil will provide for their needs. It will also aid the soil in holding onto moisture, which will prevent problems such as blossom-end rot. Many gardeners also add a synthetic or organic fertilizer. Some types, such as water-soluble granules or fish emulsion, can be applied when watering. There are also granular forms that can be mixed with the soil before planting or used as a side dressing, and time-release fertilizers, which can be added to the soil at planting time.
No matter what kind of fertilizer you use always follow the directions on the label. Do not over-fertilize because this will cause lush plants with little fruit set. It’s best to select a fertilizer that contains more phosphorus (P) than nitrogen (N) or potassium (K). Phosphorus promotes flowering and fruit set.
10. What causes my tomato to have lots of flowers but no tomatoes?
Often when your plants have a lot of blooms and no tomatoes it is due to the weather. When temperatures rise above 85 to 90 degrees F (depending on humidity) during the day and 75 degrees F at night, pollen will become unviable. Humidity can also come into play. In extreme humid times, pollen may become so sticky that it does not fall. On the other end of the spectrum, if it is very dry, pollen may become so dry that it does not stick to the female part of the flower. Tomatoes have perfect flowers, meaning each flower has both male and female parts and the plants can self-pollinate so pollinators are not needed for pollination.
11. How do I grow a tomato plant in a container?
For best results, select a tomato variety with a compact or determinate habit—compact cherry tomatoes are particularly good for container culture. The container needs to be deep, at least a foot, with drainage holes on the bottom. Use a sterile growing mix, keep the plants evenly watered, and place them so that they receive as much direct sunlight as possible. Feed plants regularly with a water-soluble fertilizer, keeping in mind that nutrients will leach out of the pots faster than garden soil. During periods of hot weather, full-grown plants may need to be watered daily.
12. How do I know when to harvest my tomatoes?
For the best tomato flavor, allow the fruit to fully ripen on the plant. Wait until it is deep red, yellow, or whatever final color the tomato is to be because once it is removed from the vine, the supply of sugars is cut off. To harvest, gently twist the fruit so that the stem separates from the vine. Tomatoes are best kept at room temperature and will store on a kitchen counter for several days. At the end of the season when frost is predicted, green tomatoes can be harvested and placed on a windowsill or counter. Most will gradually turn red and have some degree of tomato flavor. Placing unripe tomatoes in a paper bag will hasten the ripening process.
13. What is the best tomato to plant for home canning?
My first choice for a canning tomato would be a determinate Roma type. Determinate tomatoes produce a large amount of ripe fruit in a relatively short window of time so you would have more tomatoes to can at one time. Roma’s also are less watery, which I prefer for canning.
14. What’s the best tomato for Salsa?
While any tomato will work well in salsa, I prefer to use Roma types because they are less juicy and more “meaty”, which can mean that the salsa will not be as watery. If you want to make large batches of salsa, I recommend choosing a determinate variety because you will get a larger concentration of ripe fruit at one time. Again, though, any type can be used and fresh-from-the-garden salsa is one of my favorite things about summer.
15. Why and how do I prune my tomato plant?
The reason to prune: The goal of pruning is to create an optimal balance of vegetative growth and fruit production. Pruning can result in increased fruit size and increased earliness of the crown set. Less foliage also increases light penetration and air circulation in the lower canopy, which can reduce disease severity.
When to prune: Pruning of indeterminate tomatoes is typically done four to five weeks after transplanting. (Determinate types typically do not need to be pruned. Some say pruning makes a plant easier to work with and produces larger fruit but that is an individual choice based on specific variety and experience.) Pruning prior to the first stringing or staking simplifies the process of accessing and removing suckers.
It’s best to remove suckers when they are just two to four inches long. Removing larger suckers (thicker than a pencil) will leave large wounds that are slow to heal and can be sites for infection. Plants should be pruned when they are dry (no moisture on plant surfaces) to minimize the spread of foliar diseases.
How to prune: Prune to create one, two, or three main tomato branches through the removal of all but one or two suckers. The vines are then trained to grow on support systems. Additional suckers are removed as the vines continue to grow. Smaller suckers can be easily removed by pinching them with fingers, using a sideways, snapping motion. Larger suckers should be removed with a sharp knife or shears to prevent tearing the plant’s tissues. As the season goes on, remove all leafy suckers beneath the first fruit cluster as this prevents disease from splashing up on the lower leaves. As it gets later in the season, it’s a good idea to prune or “top” the growing tip of each main stem about four weeks before the first fall frost. This way, the plant puts its energy into ripening all remaining fruit rather than producing new fruits.
Pruning container-grown tomatoes: Container-grown tomatoes are more than likely to be a determinate or semi-determinate variety. So follow the above recommendations. There is no difference between potted tomatoes vs. in-ground tomatoes for pruning recommendations.
Bury the stem about 2/3rds deep when planting your tomato plant. This will ensure a much stronger and sturdier plant.
Still, have a question about growing tomatoes in your Victory Garden 2.0? Be sure to ask in the comments below and our NGB Member Experts will answer them for you.
Check these posts for additional tips on creating your own Victory Garden 2.0
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