The investigation was conducted in 2013-2014 in the greenhouse “Flora” in Kalynivka, Vinnytsia region.

Oval tulip bulbs were selected for the growing and they were carried into a room with controlled t⁰ and humid level. Tulips of different varieties and shape were used for the growing in order to blossom at least for a month.

Terry tulips were chosen as early flowering, Triumphal – as mid flowering and Darvin as late flowering tulips. Such varieties as Diplomat, Hudotnyk and London were chosen for early flowering. Their bulbs were cooled according to the Dutch technology (t⁰+9⁰ and +5⁰). Tulips of other varieties were chosen for mid and late terms of growing.

After the analysis of influence of t⁰ level on the duration of flowering, and obtaining of market quality flowers, we came to the conclusion that the least duration of flower forcing (37 days) was obtained at t⁰ + 18-20⁰. 5 degree Dutch technology of tulip bulbs storage was used during 3-4 weeks. The optimal t⁰ for mid terms tulip forcing is +14-16⁰ and flowering shoots duration is 45 days. To get flowers in later terms the t⁰ should be 10-12⁰ and at the same time it is possible to  supply market quality flowers of tulips on the 62d day.

Similar behaviour was observed at application 9-degrees technology of storage of bulbs of tulips.

At 9 degrees technology, bulbs, what were selected for early terms, at a given temperature kept to the first decade of October, and for the receipt of late  growing - to the middle of October. When sprouts attained  7-9 cm, and it is early to start growing, a temperature was reduced to 0-2 ℃ for 2-3 days.

At 9 degrees technology after storage of bulbs in a refrigerator for the best taking root after growing the temperature of soil is maintained  within the limits of a 10-11 ℃, air 11-13 ℃. For increasing of cutting quality growing of tulips was conducted at lower temperature 12-14 ℃. A period from planting of bulbs to flowering for the early sorts of tulips presents 6-7 weeks, and for middle and late - 8-9 weeks.

The traditional cooling of bulbs is applied at a temperature 10-12 ℃ for growing of tulips in middle and late terms. If it is needed to detain flowering of flowers a temperature goes down to 2-3 ℃, for 2-3 days. In future, till flowering¸ the temperature of air gradually rises to 17-18 ℃. For lengthening of term of flowering, receipt of an increase colouring of flowers it is necessary to low the air temperature to 12 ℃.

At application of traditional technology of receipt of commodity products of flowers of tulips duration of their growing  proceeds on the average on 3-5 days, as compared to Dutch.

The least duration of growing floriferous sprout (44 days) at the early terms of growing of tulips at a temperature condition 18-20 ℃. The same mechanism is at middle terms. At establishment of temperature condition within the limits of 10-12 ℃ in the late terms of growing of tulip the period of growing floriferous of sprout lasts 65 days.

At industrial production of tulips it is expedient to apply those technologies of growing which are possible to be managed. Dutch technology of cooling of bulbs at 9 and 5 degrees during 3 weeks allows to get flowers on a cut in the planned terms.

The least duration of growing of tulips (37 days) was received at the temperature condition of the closed soil at 18-20 ℃. For the conveyer supply of tulips in later terms (on 62d day) a temperature condition in a greenhouse it is better to maintain at the level of 10-11 ℃.

Key words: varieties of tulips, technology of growing, temperature condition, terms of growing.