|Brown Spots On Leaves and Stems||Frost Injury|
|Stems Weak; Florets Sparse||Bulbs Old|
|Foliage Distorted; Bulbs Decayed||Bulb Mites|
|Bulbs Softened; Plants Yellowed||Narcissus Bulb Fly|
|Plants Stunted; Yellowed; Root Lesions||Bulb Nematodes|
|Foliage And Buds Fail To Open||Aphids|
|Plants Stunted; Die Prematurely||Basal Rot|
|Flowers \"Break\" In Color; Petals Streaked||Mosaic Virus|
|Bulbs Gnawed; Unearthed Or Eaten||Rodent Injury|
Brown Spots On Leaves and Stems From Frost Injury
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 hyacinth bulbs right after the ground freezes.
Stems Weak; Florets Sparse Because Bulbs Are Old
Hyacinths look their best 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. Some homeowners actually prefer them this way. To keep the bulbs in the best possible condition, fertilize bulb beds with bone meal or bulb fertilizer every spring. Be sure to leave the foliage after the blossoms are spent so that it can help the bulb store nutrients for the next season.
Foliage Distorted; Bulbs Decayed Caused By Bulb Mites
Bulb mites, about 1/50 inch long, are almost invisible. They have four pairs of legs, piercing-sucking mouth parts, and very compact bodies. Below ground, they cause the infested hyacinth bulbs to become hard and light chocolate-brown colored. Hundreds of mites feed on their dry and crumbly pulp. Mite damage also opens the way for other pests and diseases. Control mites by destroying all affected bulbs. Soak any other dormant bulbs in hot water (110 to 115°F.) for 3 hours. For more information see the file on Controlling Mites
Bulbs Softened; Plants Yellowed Caused By 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.
Plants Stunted; Yellowed; Root Lesions Caused By Bulb Nematodes
Bulb nematodes and root knot nematodes sometimes attack hyacinths. Nematodes are not insects, but slender, unsegmented roundworms. Most are microscopic-sized soil-dwellers. They have piercing-sucking mouthparts and feed on plant cells. Infested hyacinths look sickly, wilted, and stunted, with yellowed or bronzed foliage. They decline slowly and die because their root systems are poorly developed, even partially decayed. Bulbs are also damaged. Dig up and trash damaged bulbs. Add lots of compost (especially leaf mold) to the soil to encourage beneficial fungi that attack nematodes. For more information see the file on Controlling Nematodes
Plants Stunted; Die Prematurely Caused By Basal Rot
This fungus disease attacks hyacinth bulbs when soil temperatures are around 65 to 75°F. It stunts plant growth and retards root development. Eventually the bottom of the bulb develops a soft brown rot. Discard any diseased bulbs and avoid injuring 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 hyacinth bulbs in the area for 3 years. For more information see the file on Controlling Fungal Disease
Flowers \"Break\" In Color; Petals Streaked Caused By Mosaic Virus
This virus disease causes flower petal color to become streaked. It weakens the hyacinth plant. Several kinds of aphids transmit viruses. Trash affected plants. Sterilize any tools used for cutting the flowers in hot water and household bleach to avoid spreading the infection. Control aphids if present, and keep weeds down.
Bulbs Gnawed; Unearthed Or Eaten From Rodent Injury
During the winter months, small rodents such as mice eat bulbs. Moles tunnel through beds in search of earthworms and insects, then mice or voles use their tunnels to get at hyacinth bulbs. Control these animals by lining your planting holes with small baskets of 1/4-inch hardware cloth cut to fit. Or, try planting individual bulbs in tin can \"sleeves\" cut open at both ends and sunk into the soil so that the top rim is just beneath the soil surface. Set the bulbs near the bottom of the can to allow the roots to spread into the soil beneath. On the surface of the soil lay one-inch wire mesh over the bulbs beds and fasten it into the soil with pegs to discourage squirrels and chipmunks from digging up hyacinth bulbs.