How To Grow Tomatoes Indoors & Take Care Of Them

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Planting your tomatoes indoors is a task that is becoming more and more fashionable every day. If you don’t have a garden, that doesn’t mean you can’t plant! Today we will let you know about How To Grow Tomatoes Indoors.

How To Grow Tomatoes Indoors

The king of the garden, the king of salads, tremendously healthy and one of the most complicated crops that we can face in the urban garden. Growing tomatoes at home can make agricultural insiders and experts desperate, but the rewards of its fruits make it worth all the effort. Here is a detailed guide from planting to the most common disease treatments, through tricks and ideas that we have been learning over the years. So, let us present you the step-by-step guide on How To Grow Tomatoes Indoors.

1. What Variety of Tomato to Choose for Indoors :

The first choice we must make when deciding to plant tomatoes is which variety we want to grow. This will depend mainly on our tastes, but there are several factors that can influence the success or failure of our harvest at this point.

Tomato to Choose For Indoors

Choose between determinate or indeterminate tomatoes-

When it comes to planting tomatoes, there are two large groups and it is very useful to know which of them the variety we are going to plant belongs to, as they have very different behaviors. They are determinate and indeterminate tomatoes.

Choose varieties resistant to diseases or pests

As a general rule, the varieties that are most resistant to pests and diseases that you may suffer are those traditional to the area. Which has already been adapted to that climate for many generations. And to the possible pests that may be encountered. Ask the farmers in the area. There are also varieties with greater resistance to certain types of diseases, such as the RAF Marmande tomato, which is resistant to fusarium.

2. How to plant Or Grow tomatoes Indoor

Grow tomatoes Indoor

To grow tomatoes at home successfully it is important to sow when it is time. Tomato sowing can be done from January (Northern Hemisphere), some varieties, such as Marmande, from December. Whenever we sow in the winter months we must do it protected, that is, with a greenhouse and indoors. It is best to opt for a heated seedbed, which will maintain the optimum germination temperature throughout the process.

Starting in March, we will be able to sow in an unprotected seedbed, although it is always advisable to use a greenhouse to conserve humidity and protect the seedbed from possible drops in temperature.
The seeds will germinate in 7-10 days.

3. The transplant

It usually occurs two months after sowing, which is when the tomatoes have already developed true leaves.

The transplant
When we carry out the transplant we must take into account certain important aspects:


  • Add compost: The plant will need extra nutrients from the first moment, this will have it covered with a good application in the compost soil.
  • Take care of the frosts: Being a crop so early it can be surprised by a sharp drop in temperatures, typical of spring. Have mini-greenhouses ready just in case.
  • Bury the stem: To favor the development of the roots (the more roots, the stronger the plant) you can bury the stem up to the first leaves. The buried part will begin to generate them in a short time.
  • The separation between crops: It depends a lot on the variety, but as a general rule they need about 40 cm of separation between plants.
  • Substrate volume: It also depends on the variety, but generally the tomato needs about 16-20 liters of the substrate if you want to grow them in a pot.
  • Tutor: Do not wait for the plant to grow, it is better to train from the beginning. Being a large plant, it can bend in the wind. In addition, its high sensitivity to ambient humidity makes trellis necessary to guarantee good ventilation between the leaves and fruits.

4. Tomato care for Indoor

  • Irrigation: Prefers deep irrigation, that reaches the lowest layers of the soil, and space.
  • Light: It is demanding in light, requires a minimum of 6 hours of sun, although its maximum productivity occurs when it receives 8-10 hours of light.
  • Nutrients: It is a nutrient-demanding crop, the best option is to continuously provide organic matter. Which will provide a balanced dose of nutrients throughout its life cycle. During flowering, it is advisable to give it a boost with a fertilizer rich in phosphorus and calcium.
  • Tomato pruning: In indeterminate varieties, it is essential to remove the suckers. Which are nothing more than the twigs that begin to grow between the stem and the secondary branches of the tomato, at an angle of 45o. These twigs would become (if you don’t remove them) into productive branches that would bear fruit. I know this sounds good. But they take a lot of energy from the main stem and you will get much smaller fruit with less flavor. So let it be better to have one with a lot of energy than one with juicy and large tomatoes.

Tomato care for Indoor

Tip: Leave the first pacifier that appears at the base. In this way, you will have two productive tomato stems. In case one of the two breaks or suffers an attack from a plague or disease. You will have to train it the same as the main branch.

5. Tomato pests and diseases

Planting tomatoes indoors or outdoor is very rewarding. But there are times when our idyllic image of a garden full of large, juicy tomatoes. The kind that tastes like the local ones, is cut short by a pest or disease. Do not take it into account. Yes, it is a delicate crop, but when things go well it is one of the most grateful.

The most common tomato pests are:


It feeds on the sap of plants, causing deformities in the fruits, stems, and leaves. As a result of their diet, they excrete a sugary substance called molasses. Which can cause us several problems:

  • The appearance of ants: they get along very well with aphids because ants offer protection to aphids against their natural predators in exchange for honeydew. With the unconditional support of the ants, the plague of aphids will increase.
  • Bold: it is a fungus that forms a black layer on the leaves and stems of plants, reducing their vigor.


Tomato pests and diseases

Treatment: Potassium soap and neem oil.


Red spider:

In addition to observing many red dots on the underside of the leaves. The most common symptoms are:

  • The appearance of yellow spots on the leaves. On some occasions, the blade can also be deformed and bulged.
  • Massive leaf fall. Especially in summer when this pest has its highest stage of activity.
  • Grayish spots on the fruits.

Spider mites appear in very dry environments, so the best way to prevent them is to maintain adequate humidity. Also, avoid fertilizers rich in nitrogen.

Treatment: Potassium soap and neem oil

Tomato caterpillars (Heliothis and tuta absolu):

It is a caterpillar that feeds on the fruits and flowers of the tomato. The best treatment is bacillus thuringiensis, which specifically attacks caterpillars in a completely ecological way.

Common tomato diseases

Powdery mildew:

Among its symptoms are yellow spots on the upper surface that begin to necrotize in the center. With a whitish powder on the underside. It is usually caused by high humidity and little aeration, which can be prevented by maintaining the necessary separation of crops and not wetting the leaves.

Treatment: Organic fungicides such as propolis, nettle flour, or horsetail.

Mildew :
Irregular, oily-looking spots that end in necrosis. Its treatment and prevention are the same as powdery mildew.

So, look! There are the full details of How To Grow Tomatoes Indoors. You can visit our Indoor Category if you are interested in Indoor Gardening. Have a good day!


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