Vegetables which are part of our meals all year round.

Bulbous vegetables belonging to the family Alliaceae, genus Allium. Among them economic importance have the following types of onions:

- ordinary onion - Allium cepa L.
- garlic - Allium sativum L.
- leeks - Allium porrum L.
- onions Chalons - Al. cepa ssp. aescalonicum
- multistory onions - Al. cepa var. proliferum
- sand (winter) onion - Al. fistulosum L.
- rezanets - Al. schoenoprasum L.
- rocambole - Al. sceodopasum L.

Botanical Characteristics

The average onion is a plant with two or three-year cycle of development. In this connection may be two distinct groups:

- For one year growing - variety of the group of the sweet onion and most of the group semi spicy onions;

- For two years of cultivation by arpadzhik - most hot onion varieties.

To a large extent, this division is conditional, because there are varieties (Trimontium, Pioneer, competitors), which can be grown as one and two-year culture.

BIOLOGICAL FEATURES

From sowing to germination the seeds are going trough undergo the following phases:

- water absorption
- swelling
- germination
- growing

The seeds require optimal moisture 70 - 85% of the optimal limit of earth moisture and a temperature from 8 to 12C, in these conditions the seeds start growing for 10 - 12 days. The onion produced from arpadzhik is grows at the same time and for a shorter time in case a of early sown - the middle of March. Germination of seeds is characterized by increased fiber and germ knee. Once the germination finishes begins a slow growing period, especially for plants obtained by direct sowing. The first to the fifth leafs are formed subsiquently. During this period, the root system is growing more rapidly, this is why it has to be fed with nitrogen and maintaine the soil moisture 75-80 percent of the PPV in order to promote growth of young plants.

During the third period begins the fast growth with the formation of the fifth leaf (at the beginning of May for the two-year and at the end of May for one year onion and continue up to the beginning and the end of June.


The plant produced its optimal number of leaves. At the end of period formation of more leaves and asimilatite start to drain the base of leaf places. During this period lukat needs abundant moisture 70-80 percent of the PPV and clear and sunny weather.

The period of formation (formation) of bulb onions when grown by a year of direct sowing begins in the longest day in the middle and second half of June, and depending on the variety continues until mid-July to early to end of July to early secondary and by mid-August to late varieties. Requirements of the plant to the soil moisture at the end of the period is smaller. Ripening of the bulb starts gradually.

Most places zasahvat external leaf, change color and become dry tegumental scales. False stem turgora gradually loses its omekva and dip.

In the period of physiological rest bulb goes after good prosahvane. Peace is the length of variety quality of the bulb determines sahranyaemostta depends largely on the ratio of disaccharides and monosaccharides, growing conditions, the period of harvesting and prosushavaneto bulbs.

After termination of the Peace in the bulbs begin growth processes that occur in prorastvane sheet from the neck and roots of dantseto.