Last Updated on September 15, 2022 by Plant Mom Care
Hyacinthus or Hyacinth is a genus of fragrant spring-blooming perennials belonging to the Scilloideae subfamily of the Asparagaceae family although the genus is originally from eastern areas of the Mediterranean, these plants have become widely naturalized in Europe, Korea, North America, Mexico, Haiti, and Cuba.
The genus was introduced in Europe during the 1500s and became so popular that it sparked Dutch growers to develop more than 2,000 different cultivars by the 1700s. Today, the Netherlands is the main commercial producer of these plants, with around 60 popular commercial cultivars to choose from.
These perennials grow from bulbs, around 6–12 inches high, and 3–6 inches wide. Each bulb features 4 – 6 long narrow leaves with 1 – 3 spikes of flowers whose colors vary from blue, white, pink, red, and purple.
The flowers are more widely spaced in wild species, with some having just two per spike and others having 6 – to 8. Cultivars developed from H. Orientalis generally produce denser spikes of flowers and are more vigorous.
The flowers are often analogous to spring and rebirth. The flower is one of the seven symbolic items used in the beautiful Haft-Seen table settings at Nowruz, the New Year celebration in Iran.
The powerful fragrance emitted by H. Orientalis flowers is one of the strongest scents in spring. While most people think it lovely, some people find the aroma to be overpowering. The flower’s fragrance is intense, even from a distance, and the spikes of intense and bright tubular flowers are eye-catching.
Planting them in autumn will make them flower in spring. The bulbs of most varieties are large and must be planted at a depth of 4 – 6 inches in the soil, with the root-end or widest part facing down and spaced about 3 – 6 inches apart. Taller varieties tend to flop — if you only plant a few bulbs, you will have to stake them to provide some support. However, if you have many bulbs, plant them close together to support each other.
Modern cultivars are among some of the easier plants to grow from bulbs—they can either be planted in gardens or containers or grown in water-filled vases without soil. Planting the bulbs in large groups will allow you to enjoy their strong scent lingering in your garden. Their flower spikes also provide a nice contrast when planted alongside other spring-flowering plants like tulips and daffodils.
Hyacinth Light Requirements
These plants can grow under either full sun or in partial shade, allowing them at least 6 – 8 hours of daily sunlight. Don’t worry about growing them under trees since they sprout, flower and fade before any nearby deciduous trees put out leaves.
Water the bulbs well after planting, continue watering them through winter if there’s no rain, but let the soil dry between watering. They will rot sooner or later if they sit in wet, cool soil. Hence, water them once or twice weekly, depending of course on the climate.
But soil drainage capacity is an important factor since their natural habitat of the eastern Mediterranean is relatively dry and this plays a role in determining watering frequency. Reduce watering by half after the foliage becomes brown. Once the foliage has become dry, stop watering.
Humidity isn’t a concern or problem for these plants, although too much dry air might cause the tips of the leaves to turn brown or stop some flower buds from opening.
These plants can survive winter temperatures in hardiness zones 4 – 8. They might need some protection in cooler zones and some chilling in warm zones, depending on the cultivar. In areas where temperatures in winter are above 60°F, dig the bulbs up, plant them in a container and keep them at 40-45°F for 6 – 10 weeks (or in your refrigerator) before replanting them outdoors.
The bulbs have to undergo a cold period to bloom properly. If you keep a potted plant in warm temperatures, then the flower stalk will appear within a week or less, however, under cooler temperatures, the flower stalk might take a month to reach its full height before it starts blooming, although cool temperatures will make blooms last much longer when the plants start flowering.
With this in mind, you can move the plants to warmer or cooler areas to initiate flowering. Ideally, these plants flower best if kept at 40–60°F during the first 3–4 weeks after planting in autumn, then at 32–40°F until spring.
These plants prefer loose, well-draining soil and are not bothered by soil pH. They cannot handle soggy or wet soil as they are susceptible to rotting. Compost-rich soil often leads to floppy stalks – go easy on adding organic matter while preparing or amending their soil.
While these plants are considered to be perennials, they usually “die” after they bloom, leaving behind their bulbs that go dormant, so repotting involves waiting for the foliage to die and repotting to a new container every 3 years or so. Wear gloves when repotting these plants as they are toxic.
Prune any remaining foliage when the leaves die naturally after the flowers fade. This usually happens in early summer, turning the container over on a solid surface and knocking out the soil gently; the soil generally takes the shape of a container.
Break apart the soil until the dormant bulb is visible. Clean the bulbs, splitting off any offshoots and keep them on a newspaper in the cold and darkroom for 3 days and keep them in a mesh bag until autumn.
Choose a new container (clay containers are better) that can accommodate all the bulbs you want to plant and fill about a third of it with suitable soil. Plant the bulbs, wide side down, and cover with soil. Water the bulbs well until water drains out, adding more soil if necessary.
These perennial plants are normally propagated from offset bulbs that grow from the “mother” bulb. While they can also be propagated by seed, it will take several years before the seedlings generate bulbs large enough to produce a flowering plant.
Offset development can be encouraged by gently “scoring” the basal plate at the bottom of the bulb with a sharp blade/knife in the shape of a cross to get 4 offsets. Plant the bulb and you will get new offsets in a few years. This method will also take a few years before the offset bulbs grow large enough to produce flowers because of this, propagating these plants is usually done by really serious gardeners.
This method is also effective in extending the life of these plants, as the vitality of the bulbs slowly diminishes in time although they will continue flowering for several years, the flowers and the bulbs will steadily shrink in size, splitting off offsets every few years will effectively keep your plants alive forever.
When the flowers fade but before the foliage turns brown, dig up a mature plant using a trowel. Wash the soil away and separate the mother bulb and offsets. Replant them immediately in well-draining soil – dense soil can be amended with sand or compost adding a little bone meal or fertilizer when planting is recommended, be patient – it could take a few years to get a good batch of flowers.
Feeding these plants is easiest when planting, add about a handful of either bone meal or regular bulb fertilizer at planting time and again when new growth appears in spring by scratching in some fertilizer into the soil and watering the plant well.
Once the flowering period is finished, cut away the flower spikes but let the leaves remain to help the bulbs store energy for the next season.
In zones 2 and 3, an application of mulch will give the bulbs a chance to survive the cold winter. No protection is needed in zones 4 – 8, however, if you live in zone 9 or above, with temperatures above 60°F, you need to dig the bulbs up and cool them artificially (see above) before replanting.
Hyacinth Common Problems
Rodents like to eat the bulbs, use commercial rodent deterrents/poisons or plant them alongside daffodils, which also deters rodents. Root or bulb rot can affect these plants if they grow in dense, poorly draining soil.
These plants are usually low-maintenance and flower easily in spring. However, feeding them when they start flowering will give them a nice boost. Feed them again when the flowers fade to prepare the bulb for the next season.
The mosaic virus can cause petal mutation, including mottled leaves infected plants have to be destroyed to stop them from spreading to other plants. Sterilize your tools after you finish.