How to Grow and Care for Pelargonium Plants

Pelargonium plants are a genus of herbaceous and mostly evergreen perennials, shrubs, and succulents. Pelargoniums are native to southern Africa and grow well in desert and mountainous areas. (In South Africa, a species of pelargonium called Pelargonium sidoides is used as an herbal remedy for respiratory infections.) These flowering plants are often grown as houseplants in window boxes and hanging baskets.

Even though pelargoniums are commonly called geraniums, pelargonium plants are not actually geraniums. Both pelargoniums and geraniums are members of the Geraniaceae family. However, pelargonium flowers in the genus Pelargonium have two upper petals and three lower petals, while geranium flowers in the genus Geraniaceae have five similar petals with radial symmetry. True geranium plants are often referred to as cranesbill, storksbill, or hardy geraniums for their relative hardiness.

There are many different types of pelargonium plants, and they are most often distinguished by their different types of leaves.

1. 1. Zonal: Zonal pelargoniums—often erroneously called zonal geraniums—have round patterns on the inside of the leaves and produce vividly colored flowers. They are often used as bedding plants.
2. 2. Ivy-leaved: Ivy-leaved pelargoniums have trailing growth similar to ivy and will grow along fences and walls. The leaves are waxy and the flowers can come in many different colors.
3. 3. Fancy-leaved: Fancy-leaved pelargoniums have wide, variegated leaves with serrated edges.
4. 4. Regal: Regal pelargoniums are shrubby plants with rounded or lobed leaves and dark purple or red flowers that typically have solid coloration with no zoning or variegation. Angel pelargoniums are a popular choice in this category.
5. 5. Scented-leaved: Scented-leaved pelargoniums—also erroneously called scented geraniums—have leaves that emit a strong scent when touched. The modern cultivars have a wide range of smells like peppermint and lemon, and the leaves are often used for potpourri or perfume.

Pelargoniums make wonderful bedding plants in a garden flower bed, though they can also be grown in pots and window boxes.

1. 1. Plant pelargoniums in the early spring. The best time to plant pelargoniums is early spring in warm climates and mid-spring after the last frost in cooler climates.
2. 2. Choose a sunny spot in your garden. To help your outdoor plants thrive, choose a spot where your plant will receive full sun.
3. 3. Use well-draining soil. Before planting potted pelargoniums, prepare a pot with well-draining potting soil.
4. 4. Give pelargoniums ample room to grow. If you’re starting from seeds, plant the seeds at least two inches into the ground and at least six inches apart. If you’re using young plants, dig a hole as deep as the root ball and space the plants one foot apart.
5. 5. Water pelargoniums regularly. Water your plants once every two to three days during the warm growing season.

There are a few gardening tips to consider when maintaining your pelargoniums to keep their colors vivid year-round.

1. 1. Control common pests. Common pests that attack pelargonium plants include whiteflies, aphids, and slugs. Remove these insects using insecticides, neem oil, or a strong spray of water.
2. 2. Prune unhealthy stems and leaves. Check your plants regularly and prune any unhealthy or damaged stems using clean shears. This will prevent the plant from getting leggy or woody and will help promote new growth.
3. 3. Deadhead your plants. Deadheading is the practice of removing any spent blooms that appear to be dying or faded. To deadhead your pelargonium plant, simply pinch and remove the flower from the stem.
4. 4. Fertilize new plants to spur growth. Fertilizing a pelargonium plant isn’t required, but giving your new plants fertilizer once every two weeks during the growing season can help them become established.
5. 5. Apply fungicides when necessary. Pelargonium plants are prone to common fungal diseases like botrytis, or root rot. Most of these diseases can be treated with the appropriate fungicide.
6. 6. Protect your plants during the winter. Pelargoniums are tender plants, meaning they are not hardy. You will need to overwinter your plants (move them inside your house or a greenhouse) if there is a threat of frost in the colder winter months.

Propagating your pelargonium plants only requires a few cuttings, a pot with soil, and a few weeks.

1. 1. Remove a plant cutting. Take a cutting from your plant just above a leaf joint off the main stem. Remove any leaves on the stem cutting.
2. 2. Prepare a fresh pot. Prepare a pot with a well-draining potting mix and push your cutting into the soil.
3. 3. Keep the cutting in partial sun. Position the pot in a location with partial sun such as a sunny window. Let the plant sit uncovered in the pot and keep it moist. Your cutting should take root within just a few weeks.

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