Ivy Geraniums Bud Problems


Originating in South Africa, the ivy geranium (genus Pelargonium, species Peltatum) bears delicate five-petaled florets in colors ranging from white, light pink and hot pink to magenta, purple and scarlet. As its name indicates, the plant has a trailing habit with ivy-shaped leaves, suiting it well to hanging baskets and window boxes. Perhaps the worst problems that can afflict these decorative plants are those that keep the buds from opening.

Worm-Borne Destruction

  • The geranium budworm (Heliothis virescens), or tobacco budworm, is a tiny caterpillar that bores into the flower bud and eats away, hollowing it out. If the flower manages to open, it is riddled with holes. On affected plants, you’ll see tiny holes in unopened buds. Difficult to see, the worms are about 1/4-inch long, have light-colored stripes running the length of their bodies, and take on the color of the part of the plant they’re eating–they also eat flowers and leaves. You may see evidence in the form of tiny brown/black pellet-like droppings on the leaves.

    These caterpillars are considered warm-weather, subtroptical pests because the pupae do not survive temperatures below 20 degrees Fahrenheit. However, the caterpillars are active in commercial greenhouses and can thus make their way into northern gardens. And the pupae can survive in potted plants brought indoors for the northern winter.

Combatting the Worm

  • Beginning with simple measures, handpick from plants any worms or eggs you’re able to see and remove affected buds, leaves or flowers (or entire plant).

    For heavy infestation, you may need to apply an insecticide; however, the geranium budworm is notoriously resistant to insecticides. One natural remedy is Bacillus thuringiensis, known as Bt, a bacterium that kills the caterpillar but is safe for animals, humans and other insects. Available in powder or liquid form, Bt kills the worms in about 72 hours. However, its effectiveness is limited, as worms already inside buds are not likely to ingest the product. Many re-applications will be required; it has no residual effects.

    Unfortunately, natural pyrethrins–derived from different species of chrysanthemum–are not effective on these budworms. Synthetic pyrethroids, such as Talstar and Scimitar, have been found most successful in combatting the worm. According to the University of Florida IFAS Extension, pyrethoids are "one of the least accutely toxic insecticides to mammals."

Maintenance Pitfalls

  • Overwatering–contrary to what you may think–causes buds to dry up and fall off before flowering.

    Excessive heat and humidity can keep buds from opening. Unlike other pelargonium species, the ivy geranium does not thrive in temperatures above 85 degrees Fahrenheit and high humidity without afternoon shade.

    Overfeeding, while it promotes vigorous leafy growth, can keep buds from flowering.

Spore-Borne Blight

  • Botrytis (Botrytis cinera), or grey mold, is caused by air-borne spores. It can damage the entire plant, including causing bud rot. The spores germinate upon contact with wet foliage and thrive in high humidity (above 85%).

    To keep your ivy geraniums free of botrytis, be sure not to overwater them. Water early in the day (before noon) rather than at night so that moisture will be evaporated rather than linger on foliage. Keep plants nicely spaced so air can circulate between them. Regularly remove dead flowers or foliage or other debris.

    For botrytis-infected plants, remove all areas that are affected. To help control it, apply copper or sulfur based organic fungicides.

Cultivate to Promote Full Flowering

  • To promote full flowering of your ivy geraniums, provide optimum cultivation. Make sure soil is well-draining and plants are well-spaced to promote air circulation. Monitor watering needs and keep foliage dry overnight. Avoid over-fertilizing–applying compost regularly is all you’ll need to meet nutrient needs.

How to Overwinter Ivy Geraniums

0 Geraniums are beloved garden and potted flowers. They come from a large family of flowering plants referred to as geraniums and pelargoniums, with flower colors from white, through pinks and corals to red. They are distinctive plants with rounded leaves, and some varieties, like ivy geraniums, have a trailing habit that makes them ideal for hanging baskets and window boxes. There are several ways to overwinter them in northern climates if brought indoors before the first killing frost.

Moderately Easy


Things You’ll Need
  • Healthy ivy geranium plants
  • Indoor area maintained above freezing
  • Small pots and light potting mix

Take Cuttings

  1. Take cuttings from stems with leaves before the first killing frost. Clip about 1 1/2 inches off the ends of healthy trailing sections with clean, sterilized scissors or clippers.
  2. Put clipped plant material into clean, clear water, cut part in water, until ready to plant in soil.
  3. Fill pots with light, loose potting soil mix and water the soil so it’s thoroughly moistened. Plant cuttings in pots.
  4. Keep potted cuttings in a well-lighted area, under plant lights if available. Light is important for the successful growth of geranium cuttings into healthy plants. Water weekly, but don’t let pots get waterlogged. With regular moisture and 8 to 10 hours of daily bright light, the cuttings will grow well all winter and be ready for the garden or deck by spring.

Bring Plants Inside

  1. If there is sufficient space and light, bring potted plants inside before the first killing frost.
  2. Trim off dried leaves and flower heads, and trim back leggy growth. Check for insects and treat any infestations with a warm soapy water wash.
  3. Keep plants well-lighted and water once a week, being careful not to over-water or let them dry out completely.

Dig up Garden Geraniums

  1. Dig up geraniums from the garden before the first killing frost.
  2. Carefully shake the dirt from the roots and tie twine or cotton string lightly around the base of the plant, leaving a 12-inch-length loose. Use this length of string to hang the plant, either on a clothes hanger or from a rack such as a garment rack.
  3. Hang the plants upside down in an area where 80 percent humidity and cool but above-freezing temperatures can be maintained throughout the winter.

How to Winterize Ivy Geraniums


Ivy geraniums are a common flower choice in the outdoor garden. They grow either in pots or in garden soil but they prefer moderate temperatures and won’t survive the cold winter months. Potted geraniums are brought indoors in the fall and will continue growing indoors. Planted geraniums need to be dug up and prepared for the winter months.

Moderately Easy


Things You’ll Need
  • Spade
  • Knife
  • Pot
  • Potting soil
    1. Dig up the geranium using a spade before the first frost in fall. Be careful not to damage the roots. Brush off the loose dirt.
    2. Cut the roots with a sharp knife so they are 4 inches long. Cut just above any nodes in the roots.
    3. Plant the geranium in a pot filled with potting soil and water thoroughly. If you are potting several geraniums, pot them close together. They won’t be growing over the winter and don’t need space.
    4. Water the geraniums only when the soil is almost completely dry.
    5. Replant the geraniums in the spring after all risk of frost is gone.