PECULIARITIES OF NUTRITION AND OF METABOLISM OF GREENHOUSE CARNATION

In trials with greenhouse carnation "SIM", carried out at the Botanic Garden of the Moscow State University, there were studied its requirements in nutrients, optimum proportions of nutrients according to growth phases, rates and terms of application of fertilizers and metabolism processes in plants.

Trials have shown that there are a number of peculiarities in nutrition of greenhouse carnation.

1. Greenhouse carnation is related to culture of nitrogen-potassium nutrition with comparatively high requirement in phosphorus.

There are 2–3 maxima during vegetation when carnation plants consume nutrients.

The first consumption maximum takes place at a time of full blossoming and beginning of blossoming, then comes some slackening in consumption of nutrients and when passing to the second blossoming consumption intensity increases once more. This is connected with biological peculiarities of plants development.

The matter is that unlike many decorative cultures of closed ground greenhouse carnation has 2–3 waves of intensive growth during vegetation coinciding with period of full buttoning and beginning of blossoming. To the time of each blossoming there take place a renewal of growth processes, a formation of new blossom-bearing sprouts for which growth and development plant consumes a large number of nutrients. That is why with every next blossoming plants requirement in nutrients increases periodically. This should be taken into account when applying fertilizers. At the initial period of growth carnation is very susceptible to nitrogen alongside with a high consumption of potassium. In a total proportion of all other elements nitrogen exceeds potassium. Optimum ratio of nutrients at this period N:P₂O₅:K₂O=43.4:17.5:40.1.

At the phase of intensive formation of flower-bearing sprouts requirement in potassium increases. Content of potassium and phosphorus in a total of all nutrients increases (N:P₂O₅:K₂O=32.1:21.2:47.7).

With passing to buttoning proportion of potassium also sharply dominates over nitrogen with relatively high level of phosphorus (N:P₂O₅:K₂O=30.6:21.6:47.8).

At the phase of full blossoming and to the time of the second blossoming requirement in potassium nutrition increases even more (N:P₂O₅:K₂O=27.8:16.7:50.8).