Tomato "Brandywine Yellow".
Great collection variety, which, because of taste, is the most popular tomato variety, including America. Must be grown in greenhouse and plastic tunnels. Late, indeterminate variety (150-200 cm). Leafs are distinctive - like potatoes. Fruit is fleshy, 0,5-1,0 kg.
* Many amateur gardeners prefer to use only organic fertilizers as fertilizers, believing that in this way they can get rid of nitrates.
Nothing like this! They were and will always be! Both in the soil and in plants. And we cannot get away from this natural process.
Nitrates are salts of nitric acid. They dissolve well in water, migrate easily and are able to accumulate in significant quantities in the root layer of the soil, and, consequently, in plants.
Nitric acid salts are widely used as effective nitrogen fertilizers: ammonium nitrate NH4NO3, sodium nitrate NaNO3, calcium nitrate Ca (NO3) 2; as well as urea (carbamide), where ammonia is often converted to the nitrate form.
When applying high doses of nitrogen fertilizers, even without nitric acid salts (nitrates), for example, ammonia, a large amount of nitrates can nevertheless accumulate in the soil as a result of the nitrification process.
It is important that nitrates do not accumulate in plants in excess amounts - this is dangerous for the human body (especially children).
Nitrates reduce the activity of digestive enzymes and cause gastrointestinal upset. A safe daily dose of nitrates is 5 mg per kilogram of body weight (for a person weighing 70 kg, the permissible dose of nitrates is not more than 350 mg). Drinking water can contain up to 45 mg / l of nitrates. Permissible levels of nitrate content in mg / kg are: in potatoes 250; in early cabbage 900, in late cabbage - 500, in carrots 250, in cucumbers and tomatoes 150, in beets - 1400, in green vegetables (lettuce, spinach, sorrel, parsley) - up to 2000, in pepper - 200, in melon - 90 , in watermelons - 60, in zucchini - 400, in onions - 80.
You can avoid the accumulation of nitrates in agricultural products if you adhere to the following rules:
1. Do not apply large doses of nitrogen fertilizers to the soil, especially if manure, peat, humus or other organic matter is often applied. Doses of nitrogen fertilizers are reduced by 40-50% if the soils are peaty.
It is better to apply nitrogen fertilizers fractionally during the growing season. Particularly effective is fractional application on drained soils, where a significant amount of nitrates is dangerous not only because of their entry into agricultural products, but also due to possible pollution of water bodies and watercourses.
2. One-sided application of any mineral fertilizers should be avoided. Plant nutrition should be balanced in all elements. Plants must have a well-developed leaf apparatus, then nitrates are actively involved in the processes of protein metabolism.
3. Periods of prolonged rains reduce photosynthetic activity and protein synthesis activity and there is a threat of nitrate accumulation. During these periods, it is better not to eat the plants raw, but to process them.
Different types of agricultural plants under the same soil and other conditions accumulate different amounts of nitrates. Lettuce, watercress, spinach, cabbage, rhubarb, radish, parsley, radish have the greatest capacity for such accumulation.
Tomatoes, eggplants, and onions are characterized by minimal accumulation. Under normal conditions, nitrates, as a rule, do not accumulate at all in the fruits of apples, cherries, plums, currants, and gooseberries. It is essential that nitrates are concentrated mainly in the vegetative organs of fruit plants (in the leaves and stems).
Vegetable plants of the pumpkin family - squash, patisson, cucumbers, melons, watermelons are characterized by an increased ability to accumulate nitrates in fruits.
From root crops, beets are distinguished by a high ability to accumulate nitrates.
In cabbage, the maximum accumulation is in the upper leaves and stump; in cucumber fruits, the content of nitrates increases from top to bottom. Their maximum is in the peel and less in the pulp. In zucchini fruits, it decreases from the stalk to its top; in the squash - from the periphery to the center. In carrots, the nitrate content in the core of the root vegetable is higher than in the outer part and decreases from the root tip to the top. Beets have a high content area - the top and the tip of the root.
Young plants of early varieties have a higher nitrate content than adult and late varieties.
The nitrate content in plants is significantly reduced during processing. When pickling cabbage - more than 2 times; in peeled boiled potato tubers - 3 times, in unpeeled boiled - only 1-2 times.
There are a number of generally accepted effective techniques to reduce the elevated nitrate content. One of them is a possible increase in the vegetation period of plants.
And one more thing: do not spare water for intensive irrigation of vegetables a few days before harvesting.