Most gardeners prefer to prepare for the summer season on their own, not trusting the quality of purchased seedlings. Preparation takes place in several stages. Seeds are prepared in advance, the time of planting seedlings in the ground is calculated, the seeds germinate, the seedlings dive and the long-awaited process of growing the seedlings itself begins.
At this stage, gardeners are faced with growing problems or plant diseases. One of the most common undesirable symptoms of both is a change in the color of the stems or leaves of seedlings, and sometimes the entire plant as a whole. Moreover, it is the changed color of the plant that will help determine the type of problem.
Why did tomato leaves turn purple?
A healthy plant has a juicy stem with leaves and a rich green color. The appearance of lilac, crimson spots on the seedling leaves below, which soon turn purple, signals that your plant is unhealthy.
Important! If you do not take action, the purple leaves will soon shrink, wither and stick to the trunk, the shoot will not grow. The stem will become stiffer and more fragile, the roots will dry out and the seedling will die.
There may be several reasons for the disease.
- Violation of the temperature regime. Tomatoes are thermophilic plants and are very sensitive to temperature extremes. For the correct development of the bush and the formation of fruits, the temperature should ideally be at least + 20 ° C.
If the soil temperature drops below + 12 ° C, and the air temperature - + 14 ° C, the plant stops absorbing phosphorus, an important trace element for its development, from the soil. The same happens at high temperatures, above + 40 ° C.
It is because of the lack of this trace element that the leaves acquire a purple hue.
- Unbalanced ground. For proper development, growth, formation of ovaries and abundant fruiting, tomatoes need to receive phosphorus. It is recommended to prepare soil rich in this trace element for seedlings initially. If the soil does not contain enough phosphorus, the plant is inhibited in growth and changes color to purple.
The same happens when the soil is acidified or alkalized. The liquid microelement becomes insoluble and ceases to be absorbed by the plant. Lack of phosphorus, in turn, leads to poor absorption of nitrogen, which also negatively affects the growth of tomatoes.
- Violation of the light regime. Lack of light in winter, as well as growing seedlings exclusively under phyto lamps, can also lead to a change in the color of seedlings to purple.
The fact is that the spectrum of phytolamp beams is limited, and for sun-loving tomatoes it is advisable to use such lamps only in addition to the main light.
- Lack of phosphorus. Tomato seedlings accumulate phosphorus during growth and consume it throughout the season.
What to do?
- Temperature conditions are fairly easy to normalize... If these are seedlings on a windowsill, place foil under the box and increase the daytime temperature in the room to 18 ° C.
If the plants have changed color after planting in the ground in the greenhouse, then it will not be superfluous to put a heater in the greenhouse until the air temperature returns to normal.
It also happens that after planting seedlings in the ground, an unexpected cooling occurs. Refer to the kind grandmother's ways. With a sudden cold snap, summer cottages of the last century were littered with three-liter cylinders. Putting a balloon on the seedlings, a greenhouse effect was formed. At one time, these little tricks helped save seedlings even from light frosts.
- Soil nutrition... The case when the temperature regime is normalized, but the leaves do not restore their green color, indicates that there is not enough phosphorus in the soil, or it has passed into an insoluble form. These causes can be corrected by using ready-made nutritional formulas that are balanced in mineral content. Moreover, you can fertilize both the soil itself and the bush itself by spraying.
For your information. It is recommended to feed the tomatoes with phosphorus 1-2 weeks before planting the seedlings in the ground. This will give the bushes the opportunity to adapt in a new place and when the temperature drops, the seedlings, although they change color, will not die.
- Fertilizing should be done carefully.... Over-saturation with phosphorus can negatively affect the growth of tomatoes.
The most popular remedy for gardeners is superphosphate fertilizer. It is also suitable for more than just tomatoes. For open ground, a dry mixture is used, which is applied every 2-3 years in spring or autumn before digging the ground. 40 grams is enough for one square meter. For seedlings, it is better to use liquid fertilizer. To do this, 20 grams of fertilizer is diluted in 10 liters of water and insisted for a day.
For foliar feeding, gardeners advise liquid fertilizers, such as Agricola. 1 spoon is diluted in five liters of water. It is not recommended to exceed the indicated dose in order to avoid leaf burns. Spray in the morning and evening in cloudy weather. The essential trace elements are absorbed through the leaves.
- Fertilizers should not be applied during a cold snap... In order for fertilizers to be fully assimilated by plants, the air temperature must be around 18 ° C.
So that phosphorus does not pass into a solid form and is assimilated by tomatoes, the soil is limed with chalk, dolomites, lime. In the fall, organic matter is introduced: compost, humus. The green manures qualitatively improve the composition of the soil. The "Baikal-M" remedy will be of great help. Microorganisms turn the soil into black soil. It can be used at all stages of growing tomatoes.
- Tomatoes love slightly acidic or neutral soil.... In addition to superphosphate, the following fertilizers are also recommended: Double superphosphate, Ammophos, Ammofoska, Nitrofoska, Potassium monophosphate. And also natural dressing, which is introduced in the form of compost: humates, bone meal, feather grass, hawthorn, thyme.
Granular fertilizers are applied directly to the root. Phosphorus, which is in the ground for about 3 years, is best absorbed.
- It is not difficult to normalize the light regime of plants.... Choose the south window. Construct foil screens and use special LED lamps in addition to this.
Preventive measures for self-growing seedlings are very important. They are aimed at strengthening and hardening seedlings and at developing immunity to diseases, pests and temperature extremes. And it is advisable to start such prevention from the seeds themselves.
Important. Before sowing seeds, soak the seeds in the Epin solution. This product strengthens the seeds and gives a powerful boost to growth.
Also it is recommended to water the seedlings not with ordinary water, but with a minimal solution of humate... To do this, mix one teaspoon of the substance with a small amount of boiling water until smooth. Then pour it into a 2 liter container of water. This is a concentrate. It can be stored for a long time.
Immediately before watering, dilute 100 ml of the concentrate with one liter of water. This weak humate solution is used for a single application.
General preventive tips:
- Soaking seeds in nutrient mixes.
- Preparation of soil rich in trace elements and low acidity.
- Regular feeding of seedlings, especially before planting in the ground.
- Compliance with light and temperature conditions.
- Timely watering and hydration.
- Preventive treatment against diseases and pests with drugs such as Hom, Zaslon, Barrier, etc.
Compliance with these measures will avoid many problems and will allow you to grow a healthy, strong and tasty crop!
We offer you to watch a video about why the leaves of tomato seedlings acquire a purple hue and what to do at the same time: