How To Grow Tomatoes Indoors And Have Them Survive In The Winter

Who doesn't love tomatoes?

Did you know that In 2019 United States was ranked number 1 in Import of Fresh or Chilled Tomatoes

US tomatoes consumption

US tomatoes consumption from 1991-2019

The only problem with that statistics is that if you live in the US most likely you are eating an imported tomato that tool a while until they got to your plate. The thing is, you can grow tomatoes indoor, and it is really not that hard.

But there is a catch…! 

Tomatoes belong to the family of crops that grow in warm seasons. The crop tends to die when cold weather arrives. Therefore, you cannot enjoy freshly homegrown tomatoes in the winters. 

The produce is going to be very small and a lot less prolific as compared to summer tomatoes. 

Therefore, you will have to plan your indoor winter tomato cultivation to ensure season-long results. Some types of tomatoes are better for home growing, and you need to go with them during your winter cultivation. 

Tomato plants are extremely sensitive to cold temperatures. So, you need to handle them with great caution to keep them alive throughout the year. In this guide, we will discuss various aspects associated with homegrown tomatoes in winters. 

Can You Grow Tomatoes Indoors?

tomato plant

When winters arrive, the growing season for tomatoes might be over but this shouldn’t stop you from keeping the fresh produce coming to your plate. With central air conditioning systems, the temperatures inside our homes are pretty much warm. This warm air circulation serves to be the perfect condition for growing indoor tomatoes.

You just need the right varieties of supplies and light conditions to confirm those plants can produce juicy fresh tomatoes. So, that’s a yes, you can grow tomatoes indoors even when it's cold outside. 

You can either find a perfect spot inside your home that is exposed to plenty of sunlight throughout the day. Or you can go for a grow tent or a grow cabinet or a box to create proper light using artificial grow lights. Both techniques can produce wonderful results.

Additionally, you can either go for a soil-based growing medium or a soilless growing medium such as water in the case of hydroponics. The process of hydroponics involves using a water-based solvent of minerals and nutrients to feed plants and help them grow. 

Instead of soil, water serves as a medium here and makes the entire indoor growing process a lot easier. It is a much favorable option to consider because tomatoes require rich soil that needs to be very high in quality.

Another advantage that hydroponic technology has over soil-based growing is that you don’t have to deal with any pests or bacteria that thrive in the soil. Therefore, you won’t have to use any pesticides or chemical-based fertilizers. So, hydroponic technology can grow more organic and healthier food. 

Can You Grow Tomatoes From Store-Bought Tomatoes?

tomato seeds

Saving your tomato seeds from the pulp and using them for growing a new batch of tomato plants indoors isn’t that big of a deal. But you need to be careful to start with the right varieties of tomatoes. Therefore, you can’t just grow tomatoes from store-bought tomatoes. 

Most of these ordinary store-bought tomatoes are not the best king for seed saving. These tomatoes are F1 hybrids. F1 Hybrids are the 1st filial offspring generation of parental plants that are of distinctly different types If you grow from these tomatoes, your batch will be different from the original plant. 

Instead of these F1 hybrids, you need to look for open-pollinated or heirloom seed varieties which you can find at different nurseries and gardening shops either online or in-store. This variety of seeds will produce a batch that will be close to the original plant. 

Of course, if you are growing for the first time, you will need to buy these seeds from a shop. Seed companies that specifically produce these varieties of seeds should be your highest priority. Therefore, always check the packing or the website for such seeds, or you will ruin the produce. Later on, you can use the seeds from your grown tomato by following the steps listed below.

You can also use an indoor growing system that can make growing tomatoes a really easy task. Some of those smart gardens have their own tomato plant pods.

How To Save Tomato Seeds?

  1. 1
    Scoop out the seeds from the tomato and spread them on paper to dry. Fermenting these seeds would be easy, and you can end up with a cleaner group of seeds. It makes the storage and trade of these seeds a lot easier. But make sure to only use fully ripened tomatoes for seed scooping. 
  2. 2
    You just need to place your tomato upright and slice it horizontally in half right through the middle.
  3. 3
    After that scoop the seeds out in a ceramic container. It will keep the seeds wet and covered.
  4. 4
    Add a couple of tablespoons of water to it. Now, cover the container with a plastic wrap and poke some holes in it using a fork. 
  5. 5
    Let it be for 5 days in a warm place somewhere but not in direct sunlight.
  6. 6
    After 5 days you will see that it has developed a layer of mold. The layer of mold can either be thick or thin and have a terrible smell, but you don’t need to worry about it. Just remove the wrap and get rid of the mold using a spoon.
  7. 7
    Now, place the container under a gentle stream of water. You will notice the seeds will sink at the bottom. 
  8. 8
    Clear the water from the top by pouring it off gently. Make sure the seeds are thoroughly rinsed. You can also use your fingers to get rid of any stuck pieces or pulp.  Use as much water as possible to get them clean.
  9. 9
    Now, place these seeds on a coffee filter to dry out any remaining water. You shouldn't use your kitchen roll for this purpose or your seeds will get stuck to it.
  10. 10
    When the seeds are completely dry, rub them on the coffee filter and store them in a plastic envelope. Keep them away from sunlight.

How Long Does It Take to Grow Tomatoes?

A tomato plant grows best when the temperature of the soil is around 55F while the air temperature is around 65F to 90F. You can grow tomatoes from seedlings in these temperatures.

An indoor tomato plant can take around 60 to 80 days to produce a fruit. And you have to be very precise in providing the plant with the conditions that are close to what it requires naturally in the outdoor environment. 

Even a slight change in the temperature or light setting can alter the results significantly. There is not much difference in the time that a plant takes to produce fruit either in the outdoor or indoor environment. But if you want to enjoy a delicious tasting fruit then you will have to provide the plant with the right conditions and pick the fruit at the right time.

How Many Tomatoes Will One Tomato Plant Produce?

The average yield per square inch for hydroponic tomatoes is around 40 pounds annually. Under optimum conditions, you can also go for a yield ranging between 46 pounds to 50 pounds per 1.4 sq. ft.

Tomato plants are very fragile and vulnerable, and you have to take a lot of care if they are in their natural soil-based conditions. The yield will depend on whether you provide it with enough nutrients and light. 

Tomato plants under hydroponic conditions will perform best with up to 16 hours to 18 hours of light daily. They also need to be watered via drip irrigation mechanism or flood & drain system. The pH range for these plants under this technique ranges from 5.8 to 6.3. You can increase the pH level by using potassium hydroxide and reduce it by using phosphoric acid. Soil pH level is very important as it influences different factors associated with the soil in the plant growth. These factors include the likes of soil bacteria, soil structure, toxic elements and availability of nutrients. 

Nutrients are most available in the range between 5.5 to 6.5. With growing numbers of bacteria and toxic elements, your plant cannot grow and will eventually die. Therefore you will have to maintain the pH levels in the soil. 

The daylight temperatures need to range between 65F to 75F while the nighttime temperature should range from 55F to 65F. 

Also, make sure to change the nutrient solution weekly (or every 2 weeks) and for maximum yield, you can pollinate your hydroponic tomato plants using a soft brush for even better yield. 

Best Tomatoes to Grow Indoors

type of tomato

You need to keep in mind, not all tomato varieties grow very well in indoor gardens. Therefore, you need to be careful when buying your seeds. For the best results, you have to go for smaller varieties of tomato plants. 

Cherry tomatoes and plum tomatoes are proven to be best suitable for indoor gardening. These tomatoes will ripen quickly as well along with the Tiny Tim and Red Robin. Apart from them, you can also go for vining tomatoes (indeterminate tomatoes) but keep in mind they will take up more space than our regular bush tomatoes (determinate tomatoes). 

No matter which type of tomatoes you go for, you have to be sure that the temperature, moisture, and light conditions are perfect or you won’t be able to get anything substantial during the harvest. 

Steps for Growing Tomatoes Indoors

There are various steps involved in the process of growing tomatoes indoors. You have to be extremely cautious if you want your plants to achieve full yield. 

Step 1: Find the Perfect Spot 

Before gardening, you will have to find the perfect spot (usually a sunny window) in your home where there is plenty of sunlight available throughout the daytime. Your tomatoes are not going to grow at all if you don’t serve them with the right conditions. So, a sunny window is key here, and make sure to place it in a south-facing window. 

Even if you are looking to grow hydroponic tomatoes you will have to provide them with proper light, moisture, and temperature to grow. Your plants will need at least 8 hours of sunlight or 16 to 18 hours of artificial light to grow properly. They need their surrounding temperature to be around 70F. You can either go for sunlight or grow lights for this purpose.

grow tomatoes indoor by the window

Step 2: Pick the Right Seeds

Again, before gardening, pick the right kind to grow tomatoes indoors. Make sure you get the most out of your harvest.

Step 3: Begin with Germination

The next step in the gardening process to grow tomatoes indoors is to plant your seeds for germination to make sure they enter into their full growth mode. Germination needs to be initiated by adding water and starting a mix or seed starter and allowing the seeds to sit for 10 days. This process is not needed in hydroponic techniques. You will have to place it directly in the pots with your potting mix. 

Step 4: Make Some Room for Them to Grow

With the traditional soil-based methods you will have to move the tomato seedlings into pots now to make sure there is plenty of room for them to grow. You need to move these pots to the sunny spot you chose for your plants to grow. 

Step 5: Make the Conditions Right

In case of growing under sunlight, you will have to change the sides of the plants that are exposed to sunlight each day so each side grows normally. Just water them when you see the soil is dry. 

You can give them additional nutrients with the help of fertilizers after every 5 weeks. In the case of hydroponic tomato plants, you only have to set the temperature, light, and moisture conditions at the beginning and make changes to them as your plants grow. 

Step 6: Pollination

Outside in the natural environment, birds and bees help in the pollination of tomato plants but indoors that is not possible. You will have to help in spreading the pollen with a soft brush or cotton swab and this is key to grow tomatoes indoors.

Step 7: Picking up

For best flavor, leave the fruits on the plants for as long as possible that means when they turn to the correct color, bright red, orange or green. If some green fall off, they will eventually ripen while stored in a warm place out of direct sunlight. You need to grab a tomato from near its stem and twist. The tomato will snap off!

Step 8: Keep the Cycle Going

When you grow tomatoes indoors, they continue to produce fruit for an extended period. So, you don’t end your experiment right at the end of your first harvest. If you take proper care of your plants, they will continue to provide you with season-long, fresh, and juicy fruit.

What Kind of Light Do I Need to Grow Tomatoes Indoors?

tomato grow light

You might have noticed that we have emphasized the fact that the surrounding conditions to grow tomatoes indoors need to be at an optimal level for the best results. And as they are warm-weather plants, it heavily relies on sunlight. 

So, light is going to be crucial to grow tomatoes indoors. Therefore, when growing indoors you have to provide them with the best light conditions as well. Artificial light or grow light can be pretty handy in this regard.

If your plants don't get enough light in the day, they will die. The optimal light in terms of lumens ranges between 7000 lumens to 7500 lumens per sq. ft. For a minimal amount of light, you need to give it at least 2000 lumens per sq. ft. 

If you are using LED lights or fluorescent lights than they need to come with a broad spectrum of colors to support the plants at different stages of life. In the case of other lights, you have to provide your tomato plant with plenty of light, so it can produce as much fruit as possible. 

But this is mandatory during the growing stage only. And at the ripening stage, the plant needs sunlight. So, during the growth stage, you need to provide the plant with ample light.

Can You Keep A Tomato Plant Alive All Year?

When growing outdoors, you will have to rip them out at the end of the season because they can’t grow in cold weather. Growing them indoors allows you to keep them alive throughout the year. 

However, you need to keep in mind that indoor tomatoes are significantly smaller than their outdoor counterparts that grow in summer (summer tomatoes). If you can move a tomato plant from outside to inside, you can extend its harvest period and overall life as well. 

With the help of the succession planting method, you can keep indoor tomatoes going throughout the year and extend the harvest as well. But of course, for the best results, you must provide indoor tomatoes with the best light and weather conditions just like their natural environment. 

With an adequate amount of light, tomato plants can generate enough energy to produce as many fruits as possible. And if the light is not right, it won’t be able to produce much energy because the light is not enough. 

Conclusion

Growing indoor tomatoes is a pretty fun job because these are the plants that don’t last an entire year. But with indoor growing, you can keep them growing the entire year. 

Indoor tomatoes need proper conditions that are close to their natural habitat and allow them to grow in plenty of light and warmer temperatures. Also, keep in mind to use the best kind of tomatoes suitable for indoor growing. 

Usually, plum tomato plants, cherry tomatoes (including Tiny Tim and Red Robin), and vining tomatoes are the top choices to be used for indoor growing. So, use the seeds of these tomato varieties for the best results. Furthermore, don’t get to harvest them when they're green, and don’t wait for them to turn red because they can ripen after the harvest as well. 

You can continue to cultivate more seeds right after the first harvest to keep the cycle going throughout the year. For the best results, don’t forget to use the right kind of seeds and also provide them with the best possible conditions closest to their natural environment. You will see juicy tomatoes growing even in winter.

About the author 

Daniel Buckner

I have been practicing indoor gardening for quite some time now, and I love writing. So why not combine those two passions into one place where I can share my experience with the world and help the other grow fresh and healthy fruits, vegetables, and herbs in their own apartment

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