Last Updated on May 12, 2021 by Kimberly Crawford
Gardeners become familiar with different types of annual geranium plants. Explore all Pelargonium’s cultivars for plant beds and container gardens, indoors and outside.
Zonal Geraniums (Pelargonium zonale)
Zonal is the general name for the large group of geraniums often found in summer gardens. Zonal refers to the ring of darker color inside the leaf margin. Flower colors available include lavender, magenta, orange, pink, salmon, red and white and variations of bi-colored flowers, too. They come in singles, semi-doubles and doubles. The plants have an upright and mounding habit and love full sun.
‘Maverick Orange’ has fluorescent orange flowers. ‘Peppermint Twist’ gets up to 14” tall; the petals are splashed with red over a white background. ‘Moulin Rouge’ has scarlet red blooms. ‘Freckles’ has pink flowers with a dark rose middle and was an All-America Selections winner for 1991.
Fancy-Leaf Geraniums (Pelargonium ‘Distinction’)
A sub-group of the zonals is fancy-leaf geraniums. Even when the flowers do not bloom the variegated leaves will stand out. These geraniums will tolerate part shade.
Geranium ‘Mr. Henry Cox’ has yellow leaves with a red ring and splashed with green and a purplish brown. The ‘Black Velvet Series’ has black leaves slightly edged with green. Choose from flowers in red, rose, salmon or appleblossom. The geranium ‘Black Velvet Rose’ was an All-America Selections winner for 2002.
Stellar Geraniums (Stellar Pelargonium)
Stellar geraniums are also part of the zonal geranium group. They are small bushy plants. The leaves and flower petals are deeply incised creating a star-shaped appearance. Stellar geraniums will tolerate less sun, especially in southern regions. Some cultivars to look for are ‘Vancouver Centennial, ‘Peppermint Star,’ ‘Chinese Cactus,’ or ‘Exotic Glitter.’
Ivy Geraniums for Hanging Baskets
Ivy geranium have waxy, succulent leaves with a trailing habit. These geranium plants are perfect for hanging baskets, placed in an east facing location, protected from hot afternoon sun. The botanical name for ivy geraniums is Pelargonium peltatum.
‘Breakaway’ is an ivy geranium that tolerates hot weather. The ‘Summer Showers Mix’ includes red, rose, lavender, plum and white colors and trails 15-24.”
Martha Washington Geraniums
Also known as regal or pansy types, with their azalea like blooms these geraniums make beautiful houseplants. Indoors, they will prefer sun from an eastern exposure but cool temperatures (air conditioning.) Outdoors, plant them in containers and set the pots where they would be shaded from afternoon sun such as near evergreen shrubs.
Scented Geraniums
Pelargonium graveolens can be used indoors or outside. They like full sun, avoiding the hot afternoon sun. Scented geraniums should be pinched back when they become leggy.
This geranium is usually grouped with herbs; the oils, leaves and flower petals are used in perfumes and potpourris. The plants are terrific in a container garden outside or indoor among houseplants. Position these geraniums where someone is sure to brush up against the aromatic leaves.
Most plants are upright, however, there are some trailing types useful in a hanging basket. Some examples include ‘Chocolate Mint’ or ‘Snowflake Rose.’ Scented geraniums come in scents such as rose, lemon, apple, orange or mint. Usually found sold among this group would be the citrosa-scented geraniums, which is perfect for a patio used to repel mosquitoes.
Annual bedding geraniums are part of the Geraniaceae family, genus Pelargonium. To further confuse gardeners the genus Geranium is part of the same family but is a perennial plant.
Basic Care for Geraniums
Annual geraniums grow and flower best in full sun and moist, well draining soil. Geraniums growing in part shade may tolerate that level of light but will not produce flowers well. Always amend soil in a garden bed with organic material before planting. In container gardens use pre-bagged potting soil or a soil-less mix.
Pelargonium, commonly called geranium, is not the hardy perennial Geranium that returns every year. The annual geranium can be planted anytime after the first frost-free date in the area. Geraniums do not tolerate frost or cold temperatures. Their foliage will become tinged with red and plant growth will be slowed.
Plant geraniums in the soil at the same level they were in the pot when purchased from the store. A gardener should follow spacing directions listed on the plant tag for the type and cultivar of the geranium. The basic zonal geranium grows with a round, mounding type habit to 12 – 20 inches tall with a 12 inch spread.
Fertilize geraniums with a timed-release fertilizer or liquid fertilizer, following directions. The fertilizer should have equal parts nitrogen, phosphorus and potassium or with phosphorus the larger number such as 20-20-20 or 15-30-15.
Water geraniums using a watering can or soaking hose, versus an overhead sprinkler. Allow the soil, in ground planting beds, to dry out between watering. Container gardens with geraniums may require watering every day, depending on the weather, but the pot should never be constantly wet or sitting in a pool of water.
Deadhead annual geranium plants to maintain healthy plants. Geraniums are susceptible to disease and insects such as stem rot and mites; a good daily/weekly clean up of plant debris is an important part of garden maintenance for annual geraniums.
Gardening With Pelargoniums
Annual geraniums come in many types. The basic zonal, regal or Martha Washington geraniums, ivy, fancy-leafed, scented, mosquito or the stellar with deep cut foliage give gardeners a multitude of choices.
Types of geraniums such as regal or Martha Washington geraniums are usually used as houseplants. They have large flowers but are not heat tolerant. When they are planted outside these geraniums usually shut down flowering as the weather heats up and will resume flowering as the temperature drops in early fall.
The geranium planted with the Dracaena, spike, and vinca vine is a traditional container planting, sometimes overused. However, it is a reliable, inexpensive plant grouping that combines vertical interest, bold color and a trailer for the container garden.
