As an essential plant in edible gardens, tomatoes are a popular choice for gardeners. They are, however, best suited for growing outdoors in warm climates that offer long growing seasons. In some areas, though, growing outdoors may not always be an option. 

Can tomatoes be grown indoors? Let’s find out! 

Can Tomatoes Be Grown Indoors?

Growing tomatoes indoors is possible, but it requires very specific conditions in order to be successful. They need a lot of heat and bright light, which makes them difficult to grow during the cool and dull months of winter and autumn. 

Growing tomatoes indoors during these times is not impossible, though! It just takes time and effort to succeed. 

Growing Tomatoes Indoors

Tomatoes are generally considered to be an outdoor-growing plant. Growing tomatoes indoors rather than outdoors is typically done in climates where it is not possible to grow them outdoors. 

Tomatoes grown outdoors are generally planted in the spring, but tomato plants grown indoors can be started at any time. In order to get regular harvests, it is best to stagger the planting time. 

How to Start Tomato Seeds Indoors

Growing tomatoes from seed indoors is not as challenging as it may sound. The seed starting process is relatively easy, but there are specific conditions that must be observed to ensure successful seed germination. 

First, prepare a container or starting tray by filling it with a pre-moistened seed-starting mix. Then, plant the seeds ¼ inch deep; it’s recommended to put 2-3 seeds per hole. The next step is crucial. Provide the right temperature conditions for germination. You can place the container on a heat mat, or put the container in a consistently warm place with a temperature range of 70-80°F. 

Tomato Varieties That Can Be Grown Indoors

There are several tomato varieties to choose from. The varieties that grow the best indoors, however, are the small patio varieties. These varieties are the best, because it’s easy to find a large enough container to house their root system and accommodate their height. 
It is easier to manage varieties that produce abundant amounts of smaller fruits. Recommended varieties include: 

  • Sun Gold 
  • Jelly Bean
  • Tommy Toe 
  • Pear
  • Juliet 

How to Grow Tomato Plants Indoors

In order to grow tomato plants successfully indoors, you will need to get the growing conditions just right. This can be tricky, but the effort is worth it in the end!

Light

Tomatoes need a lot of light in order to thrive. They require access to full sun for up to 8 hours per day. At the very least, these plants need 6 hours of direct sunlight per day. In some cases, it may be necessary to use a grow light. 

Rotate your plant’s pot daily to ensure even growth. 

Soil

Ideally, tomatoes should be grown in well-draining soil that is organically rich. The pH level should be between slightly acidic and neutral. For best results, use a good quality, all-purpose organic potting mix. 

Water

These plants enjoy a lot of water but do not like to be left in soaking or waterlogged soil. It is important to have decent drainage, including a container with drainage holes.

Keep the soil evenly moist and check the soil moisture regularly to determine when to next water your plant. If the top inch of soil has dried slightly, it is time to water your tomato plant again. 

Temperature and Humidity

The average room temperature is acceptable for tomato plants. Specifically, temperatures between 70-80°F are ideal. When it comes to humidity levels, tomato plants aren’t too fussy. 

Air Circulation

Tomatoes should be protected from very strong drafts. Keep your plant away from heating and cooling vents. In particularly humid locations, it may be necessary to run a dehumidifier near your plant to avoid the risk of it contracting fungal diseases. 

Fertilizer

These plants are considered heavy feeders and should be fed regularly. Make use of an organic, slow-release fertilizer to feed your tomato plants. Refer to the instructions on the fertilizer’s packaging for how to apply the fertilizer. 

Pruning and Maintenance

Tomatoes do not necessarily need to be pruned. However, pruning can help the plant to become more fruitful. Small stems should be pruned off to encourage the main stems to grow more fruit rather than foliage. 

Pollination

Tomatoes do not need insects for pollination as they are self-pollinating plants. Encouraging the movement of pollen is recommended, though. Shake the plant gently or place an oscillating fan near it to act as a source of wind. 

Container Size

Container size is essential when it comes to growing tomatoes indoors. You will need a container that is big enough to accommodate the length of the plant, as well as its root system. 

Ideally, containers should be a minimum of one foot deep and one foot wide, although the bigger the better. The larger the variety you choose, the larger the pot you will need. It is also essential that the pot you use for your tomato plant has holes for drainage. 

Potting and Repotting

Tomato plants do not like to have their roots disturbed. When you start your tomatoes, you should start them in the pot you plan on keeping them in. 
If you purchase seedlings, however, you will need to repot them into your new container for further establishment. Plant the seedlings just deeper than they were when they were in the seedling container. A portion of the seedling’s stem should be buried. 

How to Store Tomatoes

Store fresh tomatoes in open containers at room temperature. 

Storing tomatoes in the refrigerator or below 60°F can cause their flesh to become mushy and unpalatable very quickly. Sliced or chopped tomatoes should be stored in the refrigerator to prevent bacterial growth, though. 

If you have an unripe or under-ripe fruit, avoid storing it in the refrigerator, and keep it at room temperature in a breathable container (e.g. cardboard box) until it becomes fully ripe. 

Conclusion 

Best suited for outdoor growth, tomatoes can also be grown indoors. You just have to create the right conditions. Despite having very specific needs, growing tomatoes indoors is hugely rewarding. Once you’ve tasted home-grown tomatoes, you won’t want to go back to store-bought!