Tomato blossom drop is a problem that many vegetable gardeners experience, particularly those in hot climates. If fact, a common question that I get from my readers in the warmer states is “Why is my tomato plant dropping its flowers?”
You’ve nurtured your tomato plants with care, eagerly expecting to get a harvest of luscious, ripe fruits. So, it is naturally frustrating to see the flowers from your plant shrivel and fall off.
This happened to me last year because I got my tomato plants in too late. I know how discouraging it can be!
But fear not! Today, we’ll explore why tomato blossom drop happens, and give you some strategies to help deal with this common tomato plant problem.
What is tomato blossom drop?
Simply put, blossom drop is a phenomenon where tomato plants prematurely shed their flowers before they can develop into fruits.
When this condition happens, it is usually preceded by the yellowing of the pedicel – the slender stalk that attaches each individual flower to the main stem of the tomato plant.
The pedicel acts as a support structure, and allows the flower or fruit to grow and develop while still receiving nutrients and water from the plant. If a tomato plant is stressed, this pedicel can shrivel and turn yellow and fall off.
Blossom drop is commonly associated with tomatoes, but it can also affect several other vegetable crops, such as peppers, eggplants, cucumbers, zucchini, melons and, occasionally, beans.
Is tomato blossom drop the same thing as poor fruit set?
These two problems are related, but not exactly the same condition.
Poor fruit set is a problem caused by a broad range of factors. Blossom drop focuses just on the dropping of flowers before tomatoes form which sometimes results in low yields.
If you can fix the reasons that cause blossom drop, you will luckily still have a good harvest of tomatoes.
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Causes of tomato blossom drop and some solutions
Understanding the causes behind blossom drop is important for preventing it and getting the harvest that you want.
From environmental stressors to nutrient imbalances, several factors can contribute to tomato blossom drop, which will affect your plants’ fruit production. Fortunately, the good news is that tomato blossom drop is usually a temporary disorder and will resolve as conditions improve.
Let’s have a look at what causes this problem and how to fix blossom drop on tomatoes.
Fluctuations in temperature can cause tomato flower dropping
Even though tomatoes are a warm loving crop, they are susceptible to extremes in temperatures.
Ideal temperatures for pollination and good growth range from 70°F (21°C) and 85°F (29°C). If you encounter extreme heat or cold, it can trigger blossom drop.
Tomato plants can take extreme temperatures, outside of this ideal range, for short periods. However if this goes on for too long it can cause the plant to go into survival mode, causing the flowers to drop.
To avoid this, plant your tomatoes after the danger of frost has passed. If you find that you planted them too early, consider floating row covers to protect plants from extreme cold.
Shade cloth (lightweight – 30%) will be useful in keeping the plants protected from excessive heat.
If your garden is in a windy area, use a barrier to prevent flowers from drying out.
Poor pollination and blossom drop
Tomatoes are self-pollinating. They have what are called “perfect flowers” – those that contain both male and female components.
However, tomato flowers still rely on wind and vibrations from insects to facilitate pollination. Insufficient pollination, often due to lack of wind or bee activity, can result in blossom drop.
Additionally, excessive humidity (either high or low) can hinder pollen transfer, leading to poor pollination.
Encourage pollination by planting pollinator-friendly flowers nearby.
Gently shaking tomato plants can aid in pollen transfer. The best time to shake the plants is mid-day when temperatures are warm and the humidity is lower than later in the day.
Hand pollinating with a Q-Tip, or a pollination brush, from flower to flower is an option if you have only a few plants.
Nutrient imbalance
Imbalances in soil nutrients, particularly nitrogen, phosphorus, and potassium, can contribute to blossom drop. Fertilizing too much, especially if your fertilizer has excessive nitrogen can encourage leaf growth at the expense of flower and fruit development.
Conversely, inadequate phosphorus and potassium levels can limit flower formation and retention.
This is an easy fix! Be sure that the fertilizer you choose is one that is balanced and meant for tomatoes, and not heavy in nitrogen.
It might be useful to do a soil test to learn about your soil’s nutrient levels and amend as necessary to ensure a balanced ratio of nitrogen, phosphorus, and potassium.
Your local department of agriculture will do inexpensive soil tests or you can purchase a soil testing kit.
Improper watering can lead to blossom drop
Inconsistent watering practices, such as overwatering or underwatering, can stress tomato plants and cause blossom drop. Water stress interrupts the nutrient uptake and can lead to flowers being aborted.
Water your tomato plants consistently, keeping the soil evenly moist but not waterlogged. Avoid watering from overhead. Instead use drip irrigation or soaker hoses.
Mulching around plants will help retain soil moisture and regulate temperature.
Pests and diseases
Certain diseases, such as bacterial wilt, fusarium wilt, or tomato spotted wilt virus, can cause tomato plants to drop flowers prematurely.
Likewise, infestations of pests like aphids, mealybugs, or spider mites can stress plants and interfere with flower development.
Monitor your tomato plants regularly for signs of disease of pest infestation, and take prompt action to control outbreaks. Practice crop rotation and sanitation to reduce the risk of disease recurrence.
Genetic factors
Some tomato varieties are more prone to blossom drop than others due to genetic predispositions. While no tomato variety is entirely immune to blossom drop, some cultivars are more resilient and less prone to experiencing this issue.
When selecting tomato varieties, especially if blossom drop has been a recurring problem in your garden, look for those known for their resistance to blossom drop or overall vigor.
Here are a few tomato types that are often reported to be more resistant to blossom drop. You can also print this list out in the card at the bottom of this post.
- Tomatoes bred specifically for heat tolerance are good choices. Examples include ‘Heatmaster,’ and ‘Sun Gold.’
- Determinate tomato varieties tend to set fruit over a shorter period, which may reduce the risk of blossom drop compared to indeterminate varieties. Examples include ‘Roma,’ and ‘Early Girl.’
- Certain tomato varieties are specifically bred for container gardening and may exhibit better adaptability to environmental stressors, including blossom drop. Examples include ‘Tiny Tim,’ and ‘Red Robin Dwarf.’
- While not all open-pollinated varieties are resistant to blossom drop, some heirloom varieties have been selected for their reliability and may exhibit better resilience. Examples include ‘Brandywine,’ and ‘Black Krim.’
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Discover the secrets behind tomato blossom drop in our latest blog post! 🍅🌸 Learn why your tomatoes might be losing flowers prematurely and how to prevent it. #Tomatoes #GardeningTips #BlossomDrop #HomeGarden #GrowYourOwn #PlantCare Click To TweetPin this post about tomato blossom drop
Are your tomato plants losing their flowers and not producing fruit? This post gives some solutions. For a reminder, pin this image to one of your gardening boards on Pinterest so that you can easily find it later.
You can also watch our video on YouTube!
Printable - Tomato Varieties Resistant to Blossom Drop
Have you noticed that your tomato plants are dropping their flowers before the fruit sets? You may be experiencing blossom drop on tomato plants.
While no varieties are completely resistant to this tomato plant problem, some are more unlikely to encounter it.
Print out this shopping list and add it to your garden journal for reference when you go shopping for tomato seeds.
Materials
- Heavy card stock or printer paper
Tools
- Computer printer
Instructions
- Load your printer with heavy card stock or printer paper.
- Choose portrait layout and if possible "fit to page" in your settings.
- Take the shopping list with you the next time you go plant shopping for tomato seeds.
Notes
Using this print function on this card will print a calendar that fills about 3/4 of an 8 x 11 sheet of paper.
To fill the entire page, choose "fit to page" on your printer if you have this setting, or use the link in the post above and print using the browser print feature.