What Is Wrong With My Grape Hyacinth?

Do the leaves have a mottled or speckled appearance, and flowers "break" in color?

Are the leaves curled and distorted?

Are the plants stunted and yellowed and do the roots have lesions on them?

Is the foliage distorted and the bulbs are decayed?

Are the bulbs softened and plants are yellowed?

Are the plants stunted and die prematurely?

Are there any brown spots on leaves and stems?

Are the bulbs gnawed, unearthed, or eaten?

These symptoms often indicate viral disease - Mosaic virus. Grape hyacinth is susceptible to yellow mosaic and cucumber mosaic virus. Afflicted plants are unproductive. Remove and destroy infected plants. Control aphids as they are the most likely carriers of the mosaic virus.

Distorted and curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

Stunted and yellowed plants with roots that have lesions on them are caused by Bulb Nematodes. Bulb nematodes are microscopic, worm-like creatures that attack bulbs. To prevent nematodes mulch regularly with compost to ensure that soil organic matter levels remain high. Heavily infested plants can only be removed and replaced with some other plant species.

Likely cause for these symptoms are Bulb mites. These, almost microscopic insects feed on plants' corms and bulbs. Severely infested corms should be dug up and destroyed. Don't replant gladiolus corms in infested soil. To destroy bulb mites in infested corms, dip them into 120°F hot water for a few minutes.

Likely cause for these symptoms is a Narcissus Bulb Fly. This large hairy fly resembles a bumblebee. Its larvae live in bulbs, giving them a spongy texture and causing them to rot. Control these pests by soaking the affected bulbs for 1-1/2 hours in hot water at 110°F. Discard any bulbs that feel soft.

These symptoms are most likely caused by fungal disease - Basal Rot. This disease attacks grape hyacinth bulbs when soil temperatures are around 65 to 75°F. Discard any diseased bulbs and avoid infecting healthy ones. Dust bulbs with Benlate before planting them. Dig up bulbs in cool, dry weather, and dry them rapidly. In the event of a serious problem, do not plant any hyacinth bulbs in the area for 3 years.

The most probable cause for this is a Frost injury. Grape hyacinth leaves and stems touched by late spring frosts may show small brown spots that later merge into blotches. Then, sometimes the leaves split and look ragged. Prevent this by spreading a 2-inch layer of mulch over grape hyacinth bulbs right after the ground freezes.

These symptoms usually indicate rodents. Mice or voles often use moles tunnels to get to the grape hyacinth bulbs. Control these animals by lining your planting holes with small baskets of 1/4-inch hardware cloth cut to fit.

If your grape hyacinth stems are weak and the florets are sparse, the bulbs might just be too old. All hyacinths look their best in the first season of bloom. While they may come up in subsequent seasons, their blossoms have fewer florets and they are not as stiffly upright.