Maximum Yield USA 2009 June | Page 39

Dwarf sunflowers have varieties which are pollen free ideal for indoor gardens and growers with allergies. Most Popular Dwarfs While there are many flowering plants, annuals and houseplants that are naturally small and short, the true ‘dwarfs’ are those which originate from tall cut flower species, but have been bred down to size. Some good examples of these are the dwarf or pot plant, Helianthus (Sunflowers) cultivars, some of which, despite their short stature, have huge yellow blooms. Other examples include sweet peas, Zinnia, Gerbera, Snapdragons, Chrysanthemums, roses, flowering stock and carnations. More recently, dwarf versions of the popular cut flower Lisianthus have emerged. Many other tall cut flower species also have dwarf versions so it’s worth checking with seed companies to see if a favorite flower type is available as a dwarf plant. Gerbera plants are perennials that will flower almost continuously if given ideal growing conditions and sufficient warmth. How to Keep Em’ Short Keeping dwarf flowers short isn’t difficult as their genetics take control over height; however, as with any plant, growing conditions also play a role. Many dwarf plants, despite their compact nature, need reasonably good levels of light otherwise growth will stretch and become thin and weak. Light levels similar to those provided to young tomato or capsicum plants indoors are suitable for most species as they head out of the seedling stage and start to form flower buds. Nutrition and EC control can also be used to give some growth control; hydroponic growers have a significant advantage in this area over traditional soil-mix production of potted flowering plants. By using ‘boom/bud promotion,’ high potassium/ calcium boosters, nutrient supplements, beneficial elements such as silica and other products developed for flowering plants at the right stage, some truly magnificent blooms and flowering plants can be grown. Careful use of root zone EC control can also help restrict vegetative growth in favor of flower development while at the same time providing maximum nutrition for a long vase life of the blooms either on the plant or after cutting. While many of the true genetic dwarfs, in particular the F1 hybrids of many species, don’t need any form of plant training or manipulation and will branch naturally, some species do benefit from some light pinching back of the growing tips. Removal of this apical dominance forces the plant to produce many side shoots, all of which should produce flowers, giving a more bushy plant and better display of color. However, not all species respond well to this and it’s a good idea to check the production guidelines given by seed companies about pinching and trimming. In the past, growth retardant sprays were widely used in the nursery industry to produce short and compact flowering plants on varieties that were naturally tall. These days, with advances in plant breeding and the production of true genetic hybrid dwarf flower types, this is a much less common practice, although there is still potential there for use of these plant growth compounds MAXIMUM YIELD USA - June 2009 39