With all-new genetics, Presto is a uniform, compact, dark-leafed zonal geranium series. These varieties produce a strong first flush of flowers — three to four blooms. No PGRs are needed with Presto geraniums. This cool-season plant also shows excellent heat tolerance, so it’s ideal for late-season and second turns.
Geraniums are best rooted in a media in strip form to allow for maximum air flow and avoid foliage overlap. After initial hydration, careful misting is required to optimize callus and root initiation. Mature leaves should show slight wilting at midday and regain turgor in the late afternoon under ideal mist conditions. Leaf petiole wilting indicates undermisting. Overmisting leads to Botrytis. Remove flower buds at transplanting.
When finishing, keep day temperatures at 65° to 76° F and night temperatures at 62° to 67° F. Fertilize with 225- to 300-ppm nitrogen. Optimum light level is 3,500 to 6,000 foot-candles.
Common diseases include Botrytis, Pythium and Xanthomonas. Scout for fungus gnats, thrips, aphids and mites.