Growing Geraniums: Tips For The Care Of Geraniums

Native to the hot climate of South Africa, geraniums are a beautiful perennial in many other areas of the world. Also known as bed and zonal geranium, this attractive and familiar flower is a popular annual and container plant, prized for its use in hanging baskets and window boxes. 

Aside from the gorgeous flowers, one reason it is so popular is how easy geranium care is. With just a little basic maintenance, you can enjoy colorful blooms all through the growing season.

Quick Geranium Facts:

• Botanical name - Pelargonium x hortorum
• Height - 1 to 3 feet (30.5 to 91.4 cm)
• Spread - 1 to 3 feet (30.5 to 91.4 cm)
• Sun exposure - Full sun to partial shade
• Soil requirements - Rich, well-drained
• Hardiness zones - 10 to 11 (as perennials)
• When to plant - Spring, after last frost

Planting Geraniums

The easiest way to plant geranium is from transplants, which are easy to find at nearly every garden center in spring. You’ll find cultivars propagated by seed, which are largely varieties with the single flower form. Since these plants must be protected from cold, wait until the threat of frost has passed before planting.

Space plants about 8 to 12 inches (20-30 cm) apart, and around the same depth as their original planting pots. Mulching the plants is also recommended to help retain moisture.

Geranium Light Requirements

Geraniums grow best in full sun but will tolerate some shade, especially at the hottest time of day. They should get 4 to even 8 hours of direct sunlight per day. Depending on where or how you grow geranium plants, their needs may differ.

When growing indoors, geraniums need lots of light for blooming but will tolerate moderate light conditions. They also need indoor temps of around 65-70 degrees F (18-21 C) during the day and 55 degrees F (13 C) at night.

Geranium Water Needs

Grown indoors, geraniums should be watered deeply once the soil feels dry.

Water geraniums when the top inch or two (2.5 to 5.0 cm) of soil is dry. In hot weather, outdoor potted plants may need daily watering. Geraniums tolerate dry soil better than wet, so avoid overwatering, and be sure to plant them in well-draining soil. They do not thrive in clay soil. When growing geraniums outdoors, moist, mix well-draining indoor potting soil with equal amounts of soil, peat, and perlite.

Fertilize your geraniums with a water-soluble houseplant fertilizer or a 5-10-5 fertilizer with additional organic matter every four to six weeks throughout their active growing season.

How to Prune a Geranium

Geraniums require very little maintenance to grow well. Deadhead spent geranium blooms to keep plants flowering, and pinch off stems to encourage branching. Otherwise, you don’t really need to prune a geranium to keep it happy and thriving.

Pests, Diseases & Problems

The most common problems with geraniums involve overly wet conditions. If your environment is hot, humid, and rainy, you might see rot and mold. To avoid these problems, space your plants for good airflow, avoid overwatering, and remove plant debris from the surrounding soil. Water geraniums gently at the soil line to keep the foliage dry and to avoid letting soil splash onto the plants.

Common infestations include aphids, whiteflies, and mites. They are more of a problem on houseplants, so watch out for early signs of pests.

Geranium Propagation Tips

Geraniums from Cuttings

The easiest and most foolproof way to propagate a geranium plant is by cuttings. If you live in a warm climate, take cuttings in early summer and plant them as soon as they root. If you grow geraniums as annuals, take cuttings in late summer or early fall. Root them in water and bring them indoors for the following spring.

Grow Geraniums from Seed

You can grow geranium from seed, but they mature slowly. You’ll need at least 8 to 10 weeks before the last frost date to get them started. Otherwise, plant rooted cuttings or transplants outside after the last frost. Geraniums are also easily propagated by taking cuttings, and some varieties must be propagated this way to ensure the right characteristics.

How to Overwinter a Geranium

When growing them as annuals, most gardeners simply buy new geraniums each spring. A more cost-effective option is to overwinter your favorite plants. One way to do this is by taking cuttings.

You can also bring a geranium indoors as a houseplant before the first frost of fall. Place it in a cool spot with bright, direct sunlight and reduce watering for the winter.

Another geranium overwintering option that will provide more vigorous blooming in the following growing season is to bring the geranium inside and allow it to go dormant. Place a potted geranium in a cool, dark part of the house that will not get cold enough for frost. A garage or basement is ideal.

Types of Geranium Plants

There are four main types of geranium flowers used in modern gardens.

• Most commonly grown as annuals and in beds are zonal geraniums. These are named for the different zones of color in their leaves. The flowers are usually white, pink, salmon, or red.
• Ivy-leafed geraniums have leaves that resemble ivy and a trailing growth habit.
• Scented-leaf geraniums have interesting aromas, including varieties that smell like rose, apple, peppermint, or citronella. Their flowers are not showy.
• Regal, or Martha Washington geraniums are most often used as houseplants.