Growing tomatoes 26.10.2018

Hardening tomato seedlings

Hardening of seedlings

Tomatoes is one of the crops that loves warmth and is very afraid of frost. To avoid a situation where you have grown a powerful beautiful seedlings, and when planting in open ground, she immediately withered, it is necessary to harden the seedlings and seeds. Hardening will provide the plant with good immunity. In the future, these bushes will give excellent harvest.

Why temper seedlings?

The essence of hardening is to make plants accustomed to exist in different weather conditions. Since the plant grew in a greenhouse or in a room where it is not typical sudden temperature fluctuations, drafts and strong gusts of wind, after landing it in the soil it may die. To this did not happen, you need to perform hardening.

Buying hardened seedlings

Choosing seedlings for the purpose of acquisition, you should know the characteristic features of hardened plants. Here are some signs by which you can distinguish hardened seedlings from normal:

  • steadily worth;
  • the dark greenish tones of the leaves are slightly purple;
  • the stem and leaves are often covered with villi;
  • the first brush of the ovaries is located above the first leaf;
  • ovaries are formed through each leaf.

Hardening your own seedlings

In order not to risk and not acquire poorly seasoned tomato seedlings, you can temper it yourself. The hardening process consists of several stages.

The first stage is hardening of seeds. If you have the seedswhich lie a few years, it is best to take them. If there are no such seeds, then it is better to keep the new seeds in a closed container in a dark, cool place. On the eve of hardening The following manipulations are performed on seeds.:

  1. Choose the largest seeds.
  2. Throw the seeds into the water, those that surfaced, discard.
  3. Disinfect seeds using 3% hydrogen peroxide for 8 minutes or 1% solution of potassium permanganate for 20 minutes.


Place cotton fabric in the container and leave the edges to cover the seeds with them in the future. Fill with water 1 cm high. If necessary, you can add a small amount of Fitosporin, it has a disinfecting effect. Then a day the seeds are in the room the next day in the fridge. And so it is replaced by heat and cold, 2 more days. After the activities done, plant seeds into the ground.


Water should not be completely frozen, but only slightly covered with a crust of ice.

Benefits of hardened seeds:

  • the first rudiments appear after 2 days and immediately with the leaves up;
  • can be planted in the ground 2 weeks earlier than ordinary seeds;
  • yield will increase by 2 times;
  • flower brush develops in one leaf and 4 days earlier than usual.

The second stage is hardening of sprouted tomato seedlings. A week later, you need to irrigate the tomatoes. After the appearance of strong leaves, you can begin the process of hardening. First you need to gradually reduce the temperature by opening the vents for 3-4 hours in the room where the plants are located. It is recommended to do this in the morning or evening.In the following days, try to make tomatoes on the veranda or the street for 4-5 hours, but be sure to monitor the reaction of plants to adverse conditions. If everything is in order, every day increase the stay of tomatoes in the air for 1-2 hours. It is strictly forbidden to make seedlings on rainy and windy days. Do not forget to protect plants from direct exposure to ultraviolet rays. Before planting in the soil, make it stand for 3 days outside.


Do not water the soil before transporting the seedlings to fresh air.

What you can not do when hardening tomato seedlings

There are frequently encountered hardening errors that you should know:

  • seedlings should not be in a draft;
  • watering should be carried out only after the seedlings have been brought into the house;
  • on the first day, do not leave the tomatoes in the street all night, start small;
  • do not let the UV rays on the leaves;
  • Seeing the wilting of the leaves, immediately bring the plants into the shelter;
  • Do not leave seedlings in the rain or during strong winds;
  • stop it use of top dressing for the period of hardening.

When to start tempering

Experienced gardeners are advised to begin hardening in the winter-spring period. Below are 3 criteria by which you will understand whether or not the plant is hardening:

  1. Normally, the color of the leaves should be a light or dark green tone. If the leaves have spots of unclear nature, hardening is not worth it.
  2. The stalk of a straight and bright green tone is ready for hardening, but if it is sluggish and sags under its own weight, it is not recommended to harden.
  3. The root system must be strong and well developed. This increases the percentage to settle down on the plant in the ground.

Hardening methods

Since tomatoes are in different growing conditions or you don’t know the age of the seeds, there are different hardening methods that will help you achieve a good harvest. We will analyze each method in more detail:

  • The traditional way. 1.5 - 2 weeks before planting in the soil hardening begins. Hardening is advised to carry out at a temperature of 16-20 degrees during the daytime, and 8-15 degrees at night. Interrupt watering for a week, and transport tomatoes in a cool place in the morning and bring late in the evening. Every day, the duration of presence on the street, extend for 2 hours. After a week, seedlings move to the street for 2 hours, and every day double this time. Before disembarking, leave it outside for 3 days under the condition of good weather without frost and wind.

The best effect can be achieved if you harden not only seedlings, but also seeds.

Tomato seedling
  • Express hardening method. Tomato seedlings leave in a room with a temperature of 0 degrees for an hour. After 4 days, repeat the procedure, only now the time spent will last 3.5 hours. After that, 4 days before disembarking, repeat the procedure, only reduce the temperature to -2 degrees and leave the seedlings for 3.5 hours.
  • Hardening with snow. Place the largest seeds in a container, wrapped in cloth, sprinkle with snow on top. After complete separation, drain the water and repeat the procedure 3 times.
  • If you have already purchased tomato seedlings, but you doubt its hardening, you can carry out the procedure yourself at home. Hardening purchased seedlings consists of 3 simple steps:
  1. take the basin and half fill it with earth;
  2. put tomato seedlings in the roots of the pelvis and cover with earth to the top;
  3. fill with water and leave in a cool place for 3-4 days, then begin the process of landing.
  • Hardening tomatoes by the method of Vladimir Anderson. Collect seeds from those tomatoes that have ripened in the garden and suffered frost times. Then pay attention to the selection of large and strong seeds, throw out small ones. Consequently, you can skip the hardening process of seeds. Seeds collected under such circumstances, have strong immunity.As for the hardening of seedlings, according to the method of Anderson, seedlings need to be subjected to huge temperature drops. Ranging from 35 degrees by day to 4 degrees by night. Water such seedlings with extremely cold water.

Features hardening seedlings growing in greenhouses and pots

Since the plants from the greenhouse can not be moved, there are some features of hardening. Two weeks before planting, proceed to reduce the temperature in the greenhouse. Increase the temperature every day. Reduce the amount and intensity of irrigation. And a week before planting, completely stop watering.

Action algorithm hardening in the greenhouse:

  1. The first 3 days open the door in the greenhouse for 3-4 hours.
  2. With the onset of 4 days, lift the edges of the film by 30 cm and leave for 5 hours.
  3. Every day, lift the film more and higher and increase the length of time by 2 hours.
  4. Actually, before planting, remove the film from the greenhouse for 3 days completely.

Algorithm action hardening in pots:

In pots
  1. For ease of transport, place the pots of plants in plastic containers, if available or in pots.
  2. For two weeks, take a hardening session, bring the plants to fresh air at a minimum temperature of 10 degrees for 3 hours. Do not forget to cover the tomatoes from direct sunlight.
  3. On day 3, transport the plants outside, for 6 hours.
  4. From 4 days leave the seedlings on the street throughout the day and only at night move them to a warm place.
  5. Before planting, leave the seedling containers outside for three days.

It is important at this time to carefully monitor the condition of the seedlings, if the leaves begin to fade, lower the film and restore the old plant species. Only after recovery can you begin the hardening session again.

Signs of readiness seedlings for planting in open areas:

  1. There are 10-12 strong leaves.
  2. Plant growth 20-30 cm.
  3. The presence of 1-2 ovary inflorescences.
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Hardening tomato seedlings is a very important procedure if you want a bountiful harvest. The procedure is simple, but it requires some effort and patience from the gardener in such a process, or rather, systematic and regular implementation. By following all the rules and recommendations, you will reduce the risk of disease and stress for the plant. And in return for your efforts you will get strong bushes that will not wilt even in the most adverse conditions.

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Hardening of seedlingsHardening of seedlings

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