Answered by Betsy Holmes, Master Gardener
Geraniums (Pelargonium spp.) are native to South Africa and are grown as annuals in most parts of the United States, but they are actually tender perennials. The four common types of geraniums are scented-leaf, ivy-leaf, Martha Washington, and zonal (Pelargonium x hortorum). Zonal are the most common geraniums sold at local greenhouses. Their name comes from the colored bands, or zones, present in their leaves. Flowers grow in orange, red, salmon, pink, white, or lavender ball-shaped clusters throughout the growing season. They can be planted in garden beds or in pots. Because they are perennials, with a little care, getting geraniums to last over winter is possible and very easy.
Saving geraniums for the winter can be done in of three ways: saving plants in pots, saving plants using cuttings, and making plants go dormant.
The least labor-intensive approach is saving plants in pots. Geraniums in garden beds can be dug up and placed in pots that can comfortably fit the rootball, adding extra soil as needed to make sure the roots are completely covered. Prune the plant back by about one-third and water thoroughly. The pot should be placed in a cool, well-lit area that is not exposed to drafts or freezing temperatures. Artificial light using a lamp or fluorescent bulb placed close to the plant can be used to supplement natural light if needed. The artificial light should be left on 24 hours a day. Soil moisture should be checked periodically and water applied only when the top of the soil becomes dry. Geraniums overwintered using this method will produce fewer leaves and grow long, woody, spindly stems. However, when placed outdoors in the spring, the stems will fill with lush, green leaves and lots of beautiful blooms.
Saving plants from cuttings can be a more labor- and space-intensive method, but it will ensure an abundant stock is ready for the next spring. While plants are still green, take 3- to 4-inch cuttings from soft but not woody stems. Remove leaves from the bottom half of the cutting. Dip the bottom half of the cutting into a rooting hormone and stick the cutting in a pot filled with vermiculite, making sure the pot has good drainage and the cutting is placed far enough in to be self-supporting. Water well, allow to drain, put the pot into a clear plastic bag to keep air around the cutting humid, and place in a sunny location. The cuttings will root in 6 to 8 weeks. Once rooted, repot the cuttings in potting soil. Keep the pots in a cool, sunny location until ready for transfer outside in the spring, making sure the plants receive sufficient water.
Continued Next Week: How to Make Geraniums Go Dormant
Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings, bulbs and other plant parts. One of the most amazing things about plants is
that every cell has the ability to duplicate all parts and functions of the plant. By taking a cutting of a leaf or stem and creating the right conditions, you can create an entirely new plant that is a clone of the parent plant.
Materials: Leaf from a plant like a geranium, African violet or Christmas cactus; bottle or jar; aluminum foil, watersoluble plant fertilizer, water, knife, spoon
- Place a pinch of fertilizer in the bottle or jar. Be sure not to touch fertilizer with your hands; use a spoon!
- Fill the bottle with water.
- Cover the top of the container with a small piece of aluminum foil. Make a small hole where the leaf will fit through.
- Ask an adult to use a sharp knife to cut a leaf from your plant close to the stem.
- Stick the leaf in the hole that you made in the aluminum foil. Make sure that just the cut tip of the stem is submerged in the water.
- Keep the water level just covering the cut tip of the stem for about 3 weeks. Roots will begin to grow and your new plant will be ready to plant.