Today, breeders use all the experience that has been accumulated over hundreds of years. Many works have been written on variety studies, breeding, morphology, anatomy and cytoembryology of roses. They allow you to accurately engage in the cultivation of these flowers in various environmental and geographical conditions.
The main modern rose breeding centers are located in Western Europe and the USA. The World Catalog of Modern Roses (”Modern Roses”) is periodically issued. All these studies confirm only one thing. When cultivating roses in a closed ground, one must pay attention to the climatic conditions of the region and, according to them, adjust the conditions for growing roses in a greenhouse. Fortunately, modern technology allows us to do this without constant human intervention.
However, do not forget that the rose wants. In summer, at daytime temperatures of + 24 ° C and nighttime temperatures of + 14 ° C, roses show optimal growth of flower shoots. A drop in night temperatures causes a drop in productivity and a delay in flowering. The duration of growth and development of growing shoots under optimal conditions, depending on varietal characteristics, is 36-46 days. In 5-7 days, buds open, 18-22 days are spent on the growth of shoots and the formation of buds 3-5mm in diameter, plus 12-16 days for the ripening of buds until technical readiness.
The most effective in different environmental and geographical conditions are roses, which are formed using high pruning. They allow you to leave a significant leaf assimilating apparatus on the shoots. A lot of attention should be paid to cutting out the wilds. But there is a method that allows the growth of wild growths. In this case, only one shoot is obtained from the bush in order to grow one giant rose.
For the cultivation of grafted roses in a greenhouse with a year-round cycle, it is better to use as a rootstock. Indication “Major” (rosa indica Major). The main qualities are continuous vegetation, excellent root-forming ability and drought tolerance. It’s a shame, but as a winter-hardy stock, we can’t recommend it for cultivation in unheated greenhouses.
Important factors for the proper growth of roses in closed ground are also the intensity of lighting, watering, fertilizing and heating. Care methods have been researched by many learned botanists and breeders. More details about their works can be found in the literature.
We believe that growing roses in a greenhouse is a matter for a person in love with these flowers. And in order to get the maximum benefit from this business, you need to put your soul into it and sacrifice a lot. However, as soon as everything works like a clock and the annual yield of roses in the greenhouse begins to give a constant profit, you can relax a bit somewhere in Hawaii (with fairly large planting areas).