When producing bulb crops, height control is often required to obtain plants which are proportional to pot size. It regards particularly to forced tulips. An effective means of controlling plant height is the use of plant growth regulators. Research was conducted to define influence of flurprimidol on pot cultivation of forced tulips of ‘Arma’, ‘Ile de France’, ‘Juan’ and ‘Yokohama’ cultivars. Flurprimidol in concentrations of 7.5,  15.0, 22.5 and 30.0 mg^.dm^-3 was applied in the form of single and double spraying of the plants. The lowest plants with the shortest upper internodes resulted from double application of flurprimidol in concentrations of 22.5 mg^.dm^-3 30.0 mg^.dm^-3. The best effect in terms of inhibiting growth was achieved in case of ‘Juan’ and ‘Arma’ cultivars treated with a retardant in the above mentioned concentration. The applied dosage and frequency of application of flurprimidol are not sufficient to inhibit the growth of ‘Ile de France’ and ‘Yokohama’ tulips. It was noted that double spraying of tulips with flurprimidol in the concentration of 22.5 mg^.dm^-3 and both single and double spraying in concentration of 30.0 mg^.dm^-3 leads to the growth of the largest leaf with the smallest area index. It was also noticed that flurprimidol slows down slightly blooming of flowers and affects shortening of flower bud length.

25-33