Geranium Care
If you're planting geraniums on the ground, ensure that the plants are separated by an 8- to 12-inch wide gap. When growing in containers, purchase pots that are 8 to 12 inches wide and have drainage holes. Indoor plants require four hours of direct sunlight daily, in daytime temperatures of around 65 and 70 degrees F and nighttime temperatures of 55 degrees F.
Using a soaker hose, water the plants weekly without wetting the leaves. This enables geraniums to retain moisture, inhibits the soil from drying out and prevents the growth of fungus. You may need to water container-grown geraniums more since these dry faster. Then, apply fertilizer on ground-grown plants every four to six weeks during spring and summer.
While geraniums can grow indoors all year round, try propagating geraniums by overwintering, especially in frost-prone areas. Plant new geraniums outdoors annually or cut back the plants by one-third during the fall, before temperatures reach 45 degrees F. Afterwards, move plants into containers to begin indoor overwintering. During the fall as well, start bringing outdoor container-grown plants inside.
Another overwintering method is by taking 6-inch geranium cuttings usually grown outdoors, placing these in soilless mix and transplanting these in indoor containers. Once done, move the container-grown geraniums outdoors in the spring after all danger of frost has passed.
Watering the plants adequately and not in excess is a must. Poorly drained or overwatered soil in geraniums may lead to stem and root rots, resulting in blackened and rotting stems. The risk for acquiring plant diseases like bacterial and fungal leaf spot, which causes leaf spots and drops in crowded areas, also rises.
Watch out for pests like whiteflies and aphids. The latter sucks out juice from geranium leaves and stems, and secretes a sticky substance called honeydew.
Pruning geraniums is ideal too. Frequent pruning produces geraniums with bushy growth and scented leaves, while unpruned geraniums are leggy and unattractive. Start by removing a green stem tip above a leaf using fingers or scissors. When you pinch it back or prune, retain three or four leaves on the stem so the plant produces new growth. If geraniums are blooming, remove the spent blossoms.