Horticulture Guruji
Exercise 9
To study the intercultural operations in flowers
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Roses:-
- Pinching: Removal of a part of the terminal growing portion of the stem is called pinching. This operation was found to reduce the plant height but promote axillary branching.
- Disbudding: Removal of undesirable buds is known as disbudding. Keeping only the central bud and removal of others cause the development of a quality bloom.
- Removal of young vegetative shoots: This practice, also known as deshooting, is generally followed in Hybrid Tea roses. Young vegetative shoots developing from the axils of leaves of basal and lateral shoots are removed to allow only one terminal shoot. Deshooting in cvs. Sonia and Belinda were found to increase flower production by 50 and 75% respectively.
- Defoliation: Several attempts were also made to study the effect of leaf removal on the subsequent growth and flowering of roses. Although defoliated plants produced about twice as many shoots as undefoliated, many of them were blind and the total number of flowers was less. Complete defoliation of mature and young leaves caused the atrophy of almost all flower buds. Removal of only mature leaves caused about 50% blindness. Removal of only young leaves did not cause blindness.
- Desuckering: Any sucker arising from stock should be removed from time to time.
- Removal of faded flowers: If the spent blooms are not removed in time, there is a chance of developing fruits bearing seeds. Once the hips are formed and reach the advanced stage of development, growth, and flowering is severely reduced during the season. Cutting of faded flowers forced strong laterals which produced good quality flowers.
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Chrysanthemum
- Stopping or Pinching: If the plant is stopped when it is 15 cm tall before even the break bud stage, the side shoots appear in leaf axils earlier by 2-3 weeks (first pinching is done at 4th week after planting).
The second pinching is done at (7th week after planting) by removing the first crown bud at the end of each lateral growth or by pinching the primaries before the crown bud has appeared. It will delay the flowering and produce second crown buds on secondaries.
Methods of pinching depend on the nature of the bloom to be obtained.
If only one bloom per plant is required no stopping is needed.
But if 3 or 6 stems are needed per the plant stopping is resorted too.
The tip of the main stem measuring 3 to 5 cm is removed. This stopping will encourage the lateral shoots (breaks) to develop from the leaf axils.
Three strong laterals are attained and others removed.
- Deshooting: (Thinning out): When an apical growing portion of the main stem is removed number of laterals are produced from the leaf axils on the main stem. When all of these laterals (primaries) are allowed to develop, the size of the flower produced on these primaries is decreased. Keeping in this view three strong laterals are retained and others are removed. The laterals retained for flowering should preferably consist of one central stem and two on either side of it.
Deshooting is also practiced from time to time by removing all side shoots before they attain the size of 2.5 cm. The aim of deshooting is to divert the food materials to the retained laterals.
In singles, Koreans and sprays deshooting is restricted to prevent the plant from being too much crowded.
- Disbudding: First crown bud develops at the end of each lateral which contains a maximum number of ray florets and will give the largest bloom, though may not be the best bloom. This is retained on all other growth arising from leaf axils is removed. Sometimes, the crown bud in laterals is stopped to obtain the second crown bud which arises from leaf axils.
In many cultivars, the second crown bud produces flowers of more intense colour, harder in texture, more symmetrical in the crowd. However, in most cultivars, the first crown bud produces the largest bloom. Disbudding stops as soon as flower buds appear.
In chrysanthemum, if all the buds in one stem are allowed to bloom, the flowers become smaller in size. Therefore in large flowering cultivars only one bud or stem is allowed to bloom and others are removed. The ideal time for disbudding is when buds surrounding the central bud have developed.
However in singles, Koreans and sprays no disbudding is practiced.
- Desuckering: All suckers that are arising from the adventitious buds present on the stem below the ground should be removed as and when they are produced.
The practice of desuckering does not influence the flower number but enhances the size and quality of flowers by diverting the nutrients to the flower bud.
- Staking: Laterals that are obtained after deshooting, should be staked with small split bamboo stakes inserted in the soil with a few to give support and also to see that these are spread out from each other. When buds start showing colour the bamboo stake is cut just below the basal level of the bud so that it does not obstruct the bud from developing into a perfectly shaped flower.
References cited
- Commercial Fruits. By S. P. Singh
- A text book on Pomology, Vol,1. by T. K. Chattapadhya
- Tropical Horticulture, Vol.1, by T. K. Bose, S. K. Mitra, A. A. Farooqui and M. K. Sadhu