Geraniums have long been favorite garden flowers adding bright color and beauty to sunny spaces. Gardeners appreciate their long lasting flowers, overall toughness and versatility.
Geraniums belong to the genus Pelargonium which means “stork” in Latin. The geranium flower has a long, slender fruit capsule that resembles a stork’s bill. There are over 200 Pelargonium species and many well-known hybrids. Most species originated in South Africa and were brought by ships to other countries beginning before 1600.
Geraniums offer variation in flower color, growth habit, leaf pattern, and scent. Geranium flowers come in white, pink, salmon, red, fuchsia, lavender, and bi-colors. There are double flower types and old-fashioned singles. Growth habits range from trailing vine types to upright garden forms. Leaves may be nearly circular or deeply segmented and lacy. Foliage can be solid green or include green and white, or patterned with combinations of reds, yellows, and oranges. Although the flowers have an unpleasant odor, there are scented geraniums that have very pleasant leaf aromas include lemon, orange, lime, peppermint, pineapple, nutmeg and rose.
Gardeners can easily reproduce geraniums from cuttings. The cuttings can be taken any time of year, but root most readily in spring or summer. Start with disease-free, vigorous plants to take short, terminal stem sections two to three inches long for propagation. Cuttings can be dipped in rooting hormone or stuck directly into a container with moist potting mix. Roots usually develop within 4 to 6 weeks.
The best location for geraniums in our hot southern climate is a spot that gets 2 to 4 hours of direct sun. Full sun exposure on days with temperatures above 95 degrees F in the day and above 72 degrees F in the night can result in yellowing of the foliage. During extreme temperatures, the plants grow better under light shade with morning or evening sun.
It is helpful for the health, attractiveness, and development of the geraniums to remove all old flowers and yellow leaves on a weekly basis, especially after a heavy rain. Part of the process (commonly called dead-heading) is to remove whole spent flower stems at the junction with the main stem. This helps to prevent infection of bacterial and fungal diseases. Take care to avoid damaging the main stem when removing the old flowers and leaves.
Geraniums usually benefit from fertilization every 4 weeks during the growing season. A fertilizer ratio of 1-2-1 is often recommended. Inspect plants for signs of occasional insect pests which include: aphids, white flies, caterpillars and spider mites.
From the last frost in the spring to the first frost in the fall, geraniums can brighten the garden.