While the hyacinth is generally a low-maintenance garden flower, errors made in planting, after flowering, or while watering can lead to unsatisfactory blooming.
Some mistakes can even lead to the development of disease. Here is a short list of mistakes to avoid while growing hyacinths in your garden.
1. Too-Shallow Planting of the Bulb
Plant hyacinth bulbs at a depth of six to eight inches. The roots need to reach down for water, and the stem needs buttressing at its base to support the abundant florets of each hyacinth flower.
Planting at this depth also helps the hyacinth avoid surface soil pests such as nematodes that can attack the bulb and kill it.
2. Fertilizer Feeding After Flowering
An annual dose of organic compost provides all the fertilization that hyacinths need.
Feeding with fertilizer after flowering will result in dramatic leaf growth at the expense of new blossoms.
Deadhead hyacinths only after blooming to encourage more flower development.
Avoid overwatering: it is the single most costly error in caring for hyacinths.
This plant is subject to a number of mold-based diseases, most of which happen due to damp soil with inadequate drainage.
These include yellow rot, root rot, and gray mold. If your hyacinths develop any of these diseases, you must dig them up and destroy them.
However, be sure to water the hyacinth during extended dry periods of over two weeks with less than five mm. (1/5-inch) of rainfall.
Allow the soil to dry down to a depth of two inches between waterings.
4. Cutting Back Leaves Too Soon After Flowering
Allow the leaves to continue growing after flowering, so they can produce the food that supports the next season's growth from the bulb.
The main bulb will start to wither and will produce few offsets if leaves are trimmed in midsummer.
You can cut back the flower stems, but leaves must die back slowly.
Plant some annuals or ornamental grass in front of the hyacinths to hide this foliage as it turns brown.
5. Removing Bulbs from the Garden for Winter Storage
Perennial hyacinths need the cold conditions of winter to achieve dormancy.
The bulbs consolidate the storage of nutrients during that time so they can revive and grow again in the warmer soil and air in the spring.
If bulbs are moved into warm conditions for winter, the primary bulbs and offsets will wither and fail to form roots when transplanted outdoors again.
6. Planting Too Late in the Season
To ensure blooms the following spring, plant hyacinths no later than early October.
The hyacinth bulbs need a 15 to 16-week period of cold conditions near or below 40 degrees Fahrenheit to ensure successful root development for blooming in April to May.
Avoid these mistakes in planting, feeding, watering, and trimming to help your hyacinths bloom fully in your garden for up to five years.
Healthy hyacinths will resist disease and insects more successfully than those weakened by improper care.