Tomato Plants Not Setting Fruit? Here’s Why

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unpollinated tomato blooms

Unpollinated tomato blooms start to shrivel and fall from the plant.

A lot of questions and calls come in every year about tomato plants not setting fruit. They look great and flower, but nothing happens beyond that. Unfortunately, the problem is usually not a disease or an insect — those can be controlled. This particular issue can be blamed on Mother Nature.

First, here’s a brief horticultural lesson. Tomatoes are self-pollinating, meaning they have flowers that contain both the male and female parts, so more than one plant is not needed for reproduction. The pollen falls within the flower to pollinate itself. That doesn’t mean insects and wind aren’t important, though. They can help pollinate self-pollinating plants; for example, when bees light on the yellow flowers, the buzzing of their wings helps to shake the pollen off into the flower.

All of this can be perfect and you might still be faced with tomato plants not setting fruit. Here’s why: high temperatures.

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 the extreme humid regions of the U.S., pollen may become so sticky that it does not fall. On the other end of the spectrum, in the arid regions, pollen may become so dry that it does not stick to the female part of the flower. Many gardeners try to gently shake the plant to encourage pollination, but a lot of times it is just not going to work.

If you’re faced with tomato plants not setting fruit, the best thing to do is to keep the plants healthy and fertilized. Try Bonnie Plants Herb, Vegetable & Flower Plant Food. The plants will start to produce again when the weather becomes favorable. Note, though, that heirloom tomatoes can be even fussier about temperatures than most hybrid tomatoes, and in some areas will wait until late summer or early fall to start setting fruit.

There are tomato varieties that will set more fruit than most in the heat (although extreme heat will inhibit most all of these plants from setting fruit). Heatmaster and Solar Fire are two of these varieties. For more, check out the full range of Bonnie Plants’ heat tolerant tomato varieties. Also be sure to consult our Tomatoes page for more info on planting, growing, and caring for tomato plants.

If you’re still stumped about why your tomato plants won’t set fruit — or have another question about growing tomatoes — visit our Ask an Expert page. Happy growing!

20 thoughts on “Tomato Plants Not Setting Fruit? Here’s Why

  1. I have to learn how to plant tomatoe seeds here in south Florida as Bonnie does not have the plants ready in 9 pack that Im interested in in the Julyn time frame. Having farmed in the New England and North Carolina as a home gardner, I fined that I do not do well in South Florida. The Master Gardner only know how to grow Flowers and I don’t eat flowers. So with the economy as bad as it is I like my Tomatoes. What kind od potting soil/mix do I use and how long should it take for the tomates to mature to a strong stem to trasplant in a pot or the garden. I have acess to a lot of horse manure and how much should be added to our sandy soil. I have been growing all my life (70 yrs) and find I am a failure in Florida. Any help will be realy great.

    • Hi Leonard,
      Congratulations on the commitment to growing your own food. I know you must have a lot of experience with growing in many different regions, after seeing where you have lived. One suggestion that may help tremendously is getting to know your local Cooperative Extension service. They have very helpful information specific to your region and can help you, in addition to the Master Gardeners whom you’ve met. You ask many questions in this message, so I’ll try to help here, but also keep it pertinent for other gardeners who may be reading. Our Ask An Expert service connects you with an Extension agent who can answer your questions on starting seeds and amending soil, but also know that Customer Service can be of help in finding the plants you seek at the time you mention. For seeds, do use a mix specified on the label for starting seeds, as regular potting or garden soil will be too heavy and encourage damping off. Make sure that any horse manure is properly aged and composted well — not hot! — before you add it into your garden soil. It can easily burn plant roots and do more damage than good. And most importantly, you are not a failure. You are blessed with a long growing season and need an entirely new approach than in New Hampshire. You’ll be pleased to find that you can grow many things year-round, but can also take a break in the high heat of summer. Make friends with your local garden center and get the scoop on when fresh new Bonnie plants arrive in season. Keep us posted. ~Mary Beth, Bonnie Plants

  2. Not a good year here at Lake Eufaula in SE Central OK. We’ve had almost two months of 100+ degree, temps, very high humidity, and drought. On top of that, I got off to a late start in late May. Our soil here is 95% sand, and we’re in the forest, with many trees now dieing. Rainfall has been lass than 15% of normal. I’ve got a nice 8′ x 12′ greenhouse, amended the soil before attempting planting with seeds using Miracle-Gro garden soil at 50/50 to 6″ depth, which was working well until the weather got nasty hot. Temps inside went as high as 145 degrees even with ventilation.
    Planted several types of seedlings inside due to ‘creature’ problems (pigmy rattlers, copperheads, cotton mouth, gophers, moles, grasshoppers, raccoon, squirrels, armadillo, skunk, deer, and black bear) and covered the greenhouse with shade screen. Tomato plants grew to 8 feet, but got only one delicious fruit., lots of flowers. Have two cantaloupes about golf ball size, a good sized honey dew, a watermelon about softball size, one zucchini hotdog size, and have harvested a few tasty pickling cukes. Strawberries are propagating quite well, in small planters on the bench, but berries only grew to pea size, ripened, then dried up. Eggplant, cauliflower, and broccoli plants are looking OK, but not doing much. Pepper plants are still only about 3″.
    We can’t get any good produce from markets locally, mostly starts rotting within a day of purchase, and almost no taste.
    I’m going to try this again next spring after starting heirloom seeds in February, and adding compost manure to at least 12″ depth, inside the greenhouse as well as the adjacent gardens outside. I do have 2 honey dew melons, and a watermelon outside that are near harvest size, but now the temps have gone from 100+ 2 weeks ago down to upper 30’s in the early AM and only 50’s by afternoon. The pumpkin outside has about 5 or 6 melons getting to tennis ball size, but I doubt they’ll make it to harvest size before freeze sets in, probably in about 3 weeks. I know I’ve overcrowded the greenhouse, and did it mostly to see what would grow, how it would grow, and if the various plants would be compatible with the area and each other.
    We’re retired on SS as our only income, and that doesn’t meet our monthly expenses, so buying things is out of reach. Any suggestions that might help? We really need to get more fruit and vegetables in our diets!

    • Hi Larry,
      Welcome to our site and congratulations on studiously growing your own food. It’s a very rewarding experience and always an opportunity to learn. It sounds like you have a great set up to overcome the weather and the critters. You state a lot of information and we can cover a lot of ground here (pun intended!). I would first suggest you explore our website pages for each vegetable you are growing. We do extensive “How to Grow” articles on planting, growing, fertilizing, harvesting and trouble-shooting, such as How to Grow Tomatoes or How to Grow Strawberries. In those articles, you will learn about pollination and which plants need it. For instance, your strawberries are probably suffering from lack of pollination if you are in a closed greenhouse where no bees or pollinating insects can reach the flowers. Or, there are varieties of cucumbers that don’t require pollination and do best in these conditions. Also, you can hand-pollinate the vegetables that need it, such as cucurbits. Tomatoes do not need this, though yours seem to fit the description of plants that get a lot of nitrogen in fertilizer but perhaps too much. That leads to gorgeous, tall, huge, green plants that gardeners boast about until they realize a balanced fertilizer and appropriate application leads to more blossoms and more fruits.
      Also, you may check the level of your shade cloth. While it is a great idea if you are in extreme sun and high temps, be sure that it’s not a heavier gauge shade cloth and diminishing necessary sunlight. Some vegetable plants you have can grow in slight shade, but the harvests are greatly diminished. Check out our “Gardening Basics” section of the site under the Gardening tab, and read up on current topics for October such as cool-season gardening. Join our e-newsletter for regular tips, too. And you might consider looking for our transplants in stores, in multi-packs for a cost-efficient option and a guaranteed head start. Happy growing! ~Mary Beth, Bonnie Plants

  3. These comments have helped alot. It must be the extreme heat that we have had in Maryland as to why I am getting so few tomatoes. Thanks fellow gardeners!

  4. Glad you were here to answer my question. My new heirloom is not setting fruit and I was worried. Now I know … it’s just the heat, and boy ! have we had heat. More on the way this week, too.

  5. We have had 10 plus days of 100 degree heat here in Charlotte. 3 of my 8 plants have turned yellow and are dieing. The others seem healthy. We supposed to get a reprieve later this week. Is it the heat that is causing the plants to turn yellow and die?

  6. My tomatoes are generally healthy and even though its July in central fl, I am still getting some new blooming. My problem is that I am getting a splitting across the tops (at the stem end). Its an end-rot but on the opposite end! Whats up?

    • Hi Steve,

      Splitting is very common when plants take up water after a dry spell. You can learn more about this and other odd effects on tomato fruit in our article “Tomato Quirks.” Happy growing!

      Kelly, Bonnie Plants

  7. My bonnies are full of tamatoes but they don’t seem to turn red yet. why?

    • Hi Gerrie,

      It can take a while for tomatoes to ripen from green to red. Just be patient, keep plants well watered and fertilized, and the fruit should ripen soon. Happy growing!

      Kelly, Bonnie Plants

    • Hi Irma,
      Sorry to hear that your tomatoes aren’t growing. There can be many reasons why and we can help you. Email our Ask An Expert service, with photos if possible, to share your experience. They can give localized advice to your area and conditions. Keep us posted,
      Mary Beth, Bonnie Plants

  8. My plants are about 5ft high and not a lot of tomatoes how do I stop them from getting to high so I can get more tomatoes

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