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Why Are My Tomatoes Flowering Early – 5 Things To Know

Tomato plants produce their fruit through the delicate yellow flowers that develop as the plant matures. Usually, when a tomato plant begins to flower, a gardener experiences excitement and joy as they anticipate their upcoming tomato harvest. When a tomato plant flowers earlier than expected, it can cause the gardener anxiety, wondering if the early flowering will affect the plant’s health or interfere with the success of the harvest. So when this happens, gardeners want to know why their tomatoes are flowering early?

More than a few possible reasons a tomato plant may flower early. These causes could include starting the seeds too early, misuse of grow lights when starting seeds indoors, the temperature of your soil, the nutrients you are using, or the variety of the tomato you are growing.

Knowing your growing geographical zone, the traits of the tomato you are growing, and best planting and fertilizing practices can help determine why your tomatoes are flowering early, as well as the best solutions that will lead to a bountiful harvest.  

Read on to learn more about why your tomatoes may be flowering early and best practices to prevent this from happening.   

5 Reasons Why Your Tomatoes May Flower Early

When tomatoes flower early, it can make you wonder if you’ve got all the right things in order for it to be a successful plant. There’s a method to figuring that out though, and here are 5 reasons you can consider if its happening to your plant.

Starting The Seeds Too Early: Know Your Zone

Many gardeners who live in seasonal environments choose to start their tomato plants indoors while the weather is still cool outside. This practice typically ensures healthy and hearty tomato plants that are ready to plant outside when the time is right.

However, if you start your seeds too early indoors, you may end up with tomato plants that are flowering while the plant is still relatively small and before the outside weather is ready for them.  

One solution for this cause of early flowering is being aware of the plant hardiness zone for your geographical area. Once you know your plant hardiness zone, many guides are available to help you know when it’s best to start seeds indoors and when to safely transplant tomatoes and other plants into your garden based on the region.  

Indoor Grow Light Practices

As at home gardening has grown in popularity, new processes have been developed to help ensure garden success. One technique that is being used more and more is the use of grow lights when starting seeds indoors. Indoor grow lights can result in a successful start to your tomato plants, but if misused, they can cause issues such as early flowering.  

There are many options of indoor grow lights available, so when using them, it’s essential to get to know the light you have purchased and how to best use it to produce healthy and happy tomato plants.

A high-quality indoor grow light will come with a guide that identifies its settings and best placement practices. It’s the gardener’s responsibility to read the guide and know your light source well to avoid issues such as early flowering. The light setting, timing, and placement can all have an effect on the growth of your plant.  

Soil Temperatures

The seed and transplanting guides you can find based on the zone you live in are based on multiple factors, one of which is average soil temperatures in your area throughout the year.

Typically, these guides advise you to plant tomatoes when the soil is consistently 60 degrees or higher not to affect the plant’s development. Some even say, for tomato plants specifically, soil temperatures should be 65 – 70 degrees before planting.

However, a heatwave early in the season that leads to higher than average soil temperatures could also lead to early flowering of your tomato plant. If a cold snap follows said heatwave, this can also affect the development of the plant through early flowering and then stalled growth.   

While the weather can be somewhat unpredictable in many growing zones, a soil thermometer can be helpful in monitoring temperatures so gardeners are aware of what potential challenges they may need to address. Soil thermometers can be found at most garden centers and online for a low price.  

In addition to monitoring your soil temperature with a thermometer, mulching your soil can help to maintain a more consistent temperature. Mulching helps prevent heat waves and cold snaps from altering the soil temperature as drastically, reducing the effect on your tomato plants.  

Fertilizers & Nutrients

An avid gardener myself, I get very excited each spring when the many plant fertilizer options begin to line the shelves at my local garden center. However, every nutrient option is different, and it’s super important to read and follow the specific fertilizing instructions for the product you select and the plant you plan to use it on, in this case, tomatoes.  

A common issue connecting nutrients to early flowering tomato plants is too much nitrogen. Nitrogen is an enriching fertilizer for tomatoes and other garden plants; however, too much nitrogen can cause the plant to put more energy into producing those early flowers and negatively affect your fruit harvest.

The gardener’s responsibility is to learn the best practices for the nutrient they are using and not overdo it. 

Varieties of Tomatoes & Vines

With heirlooms, beefsteaks, cherries, and so many more types of tomatoes, there are more varieties than most gardeners will ever know from memory. However, when addressing questions around early flowering tomatoes, it’s crucial to know that smaller tomato varieties will flower earlier than those that produce larger fruit.  

In addition to fruit size, the type of tomato vine can affect whether the plant flowers earlier or later in the season. It’s important to know whether you grow a determinate or indeterminate tomato plant.

Because of the viny structure of indeterminate varieties, they will typically flower and fruit earlier in the season with a shorter harvest period. Determinate varieties are larger, bushier plants that can produce tomatoes all season long if taken care of appropriately.  

While it will take an expert to know all of the possible varieties of tomatoes, it is responsible for gardening to know the growing patterns of the tomato varieties you have chosen to grow.  

Final Tips For Early Flowering Tomatoes

Most of the time, an early flowering tomato plant will not turn into a severe problem for the plant’s production of tomatoes. Taking steps to prevent early flowering ahead of time and being aware of why your plant is flowering early if it happens are valuable gardening practices.

Never pluck your tomato flowers, whether they are early, on time, or late. Every flower on your tomato plant has the potential to produce a juicy tomato, so when in this phase of plant growth, allow the plant to decide which flowers stay and which to drop.