The great value of a geranium is that it blooms and blooms. Just a few pots bring constant color. If you collect geraniums, giving all or a good part of your greenhouse to them, what a picture you will have. The flowers are handsomely diversified -red, rose, pink, salmon, lavender, blush, white, stippled, blended; single and double.
Zonals green-leaved, fancy-leaved, dwarf I have been referring only to the familiar green-leaved zonal type; do you know the fancy-leaved zonals? The varied hues of their foliage is almost as colorful as the big flowers of the plain-leaved zonals. They are fascinating to collect, especially if you select from rather definite categories, as gold-and-silver tricolors like 'Skies of Italy'; green-and-yellow bicolors or butterfly geraniums like 'Happy Thought'; yellow-and-brown class to which the delightful fairly dwarf 'Alpha' belongs; silver-leaveds like "Wilhelm Langguth'; and gold-leaveds like 'Verona'. More than fifty different fancy-leaved geraniums are available.
Quite a collection of dwarf zonals, both the easy ones with plain leaves and the more challenging, often tiny and fancy-leaved kind, can be grown on one greenhouse shelf; they are showy because most of these small plants produce sizable flowers. 'Tu-Tone' is delectable pale pink, 'Prince Valiant' bright crimson; the pink-veined 'North Star' and 'Whitecap' are quite irresistible.