Last Updated: June 20, 2023
When I grow a new plant in the garden, I like to get an idea of what to expect. Whether it is a new tomato variety, or an entirely new crop, seeing a plant’s growth stages is always helpful.
While tomatoes can differ quite a bit based on the type (cherry, globe, beefsteak, etc.), the main growth stages are quite similar. So, in this article I will share the tomato plant growth stages from seed to harvest.
Again, the exact shape and size of your tomato plants may vary based on the varieties you are growing. However, all tomatoes follow these same stages as they mature.
One important distinction to make is between determinate and indeterminate types. Indeterminate plants grow continuously, producing tomatoes regularly throughout the season. Determinate plants reach a set size, and stop growing after the first fruiting. Learn more here.
Stage 1: Seedling
Like most veggies, tomatoes start off as tiny seedlings. Tomato seeds are easy to germinate, and often sprout within 3-4 days of planting.
Known as cotyledons, the first leaves you will see are long and thin. These are not considered “true leaves.”
After a few more days, your tomato seedlings will begin forming true leaves. These will have a different appearance from the cotyledons, resembling a typical tomato leaf shape.
If you planted tomatoes last season, you’re likely to see volunteer plants from last year’s fallen tomatoes. These unintentionally planted seedlings will often pop up in early spring when the soil warms up!
Stage 2: Growth
Tomatoes grow fast! After reaching a few inches tall, they will need to be transplanted into larger containers to continue growing.
This stage is aptly called the growth stage. During the following weeks, tomato plants grow a strong main stem, a deeper root system, and more leaves and branches.
It is important that tomato plants have plenty of sunshine, water, and nitrogen at this stage to grow well. Over time, the larger leaf canopy helps generate more energy for the plant to use in the following stages.
As your plants are in the growth stage, it is important to keep them in appropriately sized containers. During this stage, you will likely harden off your plants to the outdoors, and eventually plant them in the ground or in a large pot.
Stage 3: Flowering
The timing of this stage varies widely, but eventually a tomato plant will begin to flower. These yellow blooms form along the nodes of the main stem and off sucker shoots.
These flowers will attract bees and other pollinators to your plants. This is important, because without being pollinated, your plants are unlikely to set many fruits.
Flowers form at the lower parts of your tomato plant first, working up over time. Flowers ultimately transform into tomatoes, so you should be happy to see them!
Should I prune early tomato flowers? Unless your plants are still in small pots indoors, there is no need to pinch off tomato flowers. Indeterminate types will always set more flowers as they continue to grow.
Stage 4: Fruiting
After a week or so, your flowers will lose their petals and begin forming fruits. Some flower will fall off completely, and that is natural (some flowers are not fertilized by pollinators or the wind).
Over this stage, you will watch your tomatoes transform from tiny berries into full-sized fruits. Depending on the variety, this process can take anywhere from 3-4 weeks.
Tip: It helps to keep these early tomatoes shaded from the sun to avoid sun scald. Most plants will naturally shade their fruits with the leaves. The West-facing side of the plant is typically the most vulnerable in the hot afternoon sun.
After several weeks, your tomatoes should reach their full size. However, they will remain green for several more weeks before reaching the final growth stage!
Never pick a tomato that is still green (unless you are nearing the winter). Unripe tomatoes are hard and unappetizing, having limited use in the kitchen.
Stage 5: Ripening (and re-flowering)
At long last, your tomatoes will begin to ripen on the plant. This is the most exciting stage of a tomato plant’s growth cycle, as it is time to harvest!
As your tomatoes ripen, they will change color from green, usually to red, yellow, or orange. I recommend waiting until the fruits are at least 50% changed before picking for the best flavor.
Tomatoes will continue to ripen after being picked. However, the best tasting tomatoes come fully ripened, right off the plant.
It is critical to water your tomatoes evenly at this stage. Avoid drought during the ripening process, and try to pick tomatoes before any heavy rain or irrigation. Irregular watering can cause nearly-ripened tomatoes to split open or succumb to blossom end rot!
If you are growing indeterminate plants, your tomatoes will continue to form more flowers, fruits, and ripened tomatoes, all at once. These are my favorite types of tomatoes to grow, as you can expect continual harvests right up until the first fall frost.
After the cold weather sets in, tomato plants will slow their growth rate. Eventually, cold weather will kill a tomato plant, as they are not frost-tolerant.
If you don’t mind a chaotic garden, leave a few ripened tomatoes on the soil – the seeds are likely to germinate next spring and give you new plants. However, I only recommend this with heirloom varieties, not hybrids.
I hope this article has helped you learn the stages of tomato plant growth. Tomato plants are incredibly rewarding and exciting to grow at home. Next, learn some top tips for bigger tomato yields and sweeter tomatoes in your garden!