One of the most powerful garden scents of spring comes from hyacinth (Hyacinthus orientalis) in bloom. Even at a distance, you'll notice these flowers' intense fragrance and the spikes of bright tubular flowers emerging from strap-shaped leaves. Introduced to Europe during the 16th century, hyacinth's popularity sparked Dutch bulb growers to breed more than 2,000 cultivars by the 18th century, and today there are about 60 to choose from in commercial cultivation.
Modern hyacinths are some of the easiest-to-grow perennial spring bulbs. Hyacinths will come back every year, though their flowers will diminish in vigor after a few seasons. They are best planted in the fall and have a moderate growth rate. Hyacinths can grow outdoors in the ground or pots, as well as indoors in a bulb vase filled with water. Please be careful and keep them out of the reach of kids and critters: The bulbs are toxic to humans and pets.
|Common Name||Hyacinth, common hyacinth, Dutch hyacinth, garden hyacinth|
|Botanical Name||Hyacinthus orientalis|
|Family||Asparagaceae, formerly Hyacinthaceae|
|Plant Type||Perennial, bulb|
|Mature Size||6–12 in. tall, 3–6 in. wide|
|Sun Exposure||Full, partial|
|Soil Type||Moist but well-drained|
|Soil pH||Neutral, acidic|
|Flower Color||White, blue, purple, pink, red|
|Hardiness Zones||4–8 (USDA)|
|Native Area||Europe, Asia|
|Toxicity||Toxic to pets, toxic to humans|
For the strongest and farthest-reaching scent, grow hyacinth in large groups. Hyacinth flowers also mix well with other spring-blooming bulbs, as they come in so many colors and sizes. Their spiky flower stalks make a nice counterpoint to cup-shaped tulips and ruffled daffodils.
Most varieties of hyacinth bulbs are fairly large. For spring garden blooms, plant hyacinth bulbs in the fall six to eight weeks before the first frost. They should be placed root end down (widest side down) about 4 to 6 inches deep. Give them some room to spread out by spacing them about 3 to 6 inches apart. Cover with soil, and water well.
Taller varieties can tend to flop. You can stake them if you only have a few, or plant them closer together so that they support one another.
Hyacinths like full sun to partial shade. Aim to give the plants at least six to eight hours of sunlight a day. As with all spring bulbs, hyacinths sprout, bloom, and start to fade before deciduous trees fully leaf out, so you don't have to worry about too much shade from nearby trees.
Hyacinth bulbs are not particular about soil pH, but they prefer a slightly acidic to neutral soil. They also do best in soil that is loose and well-drained; they will not tolerate wet soils. Rich soil can lead to floppy stalks, so go easy on the organic matter when preparing or amending the soil.
Water the ground well after you plant the bulbs. Continue watering into winter if there is no regular rain, but allow the ground to dry out between watering. If the bulbs sit in cool, wet soil, they will eventually rot. Check the ground by sticking your finger in, and water only when it's totally dry. Usually, this is once or twice a week, depending on your climate. Generally speaking, about 1/2 inch of water per week—combined irrigation and rainfall—will be sufficient for hyacinths. But this depends on how well the soil drains.
Temperature and Humidity
Hyacinths can be expected to survive the winter in USDA plant hardiness zones 4 to 8. They might need some winter protection in colder zones and some pre-chilling in warmer zones, depending on the variety. In zones where winter temperatures remain above 60 degrees Fahrenheit, dig up the bulbs and chill them somewhere dark and cold for six to 10 weeks before replanting.
The easiest way to feed new bulbs is to toss some bulb food into the hole at planting time. There are many fertilizers available for feeding bulbs—10-10-10 is recommended—or you can use an ordinary bone meal. Feed the bulbs a mere handful at planting and again in the spring when the new growth first appears by scratching some bulb food into the nearby soil and watering well. For the amount to use, follow the product label instructions.
Types of Hyacinth
Modern hyacinths come in many colors. Some varieties include:
- 'Hollyhock': Offers striking reddish-pink double blooms
- 'Pink Pearl': Has fuchsia petals that are edged in pale pink
- 'Woodstock': Boasts deep plum petals
- 'Blue Jacket': Features a denser bloom structure and deep purple-blue flowers
- 'Top White': Offers bright white florets that are star-shaped
How to Force Hyacinth Bulbs
It’s possible to force hyacinth bulbs indoors into early blooming. Simply plant a bulb in a container filled with well-draining potting mix, ensuring that the container also has drainage holes. The bulb tip should be just above the soil line. Place the container in a dark spot that remains between 33 and 45 degrees Fahrenheit. Allow it to sit there for at least 10 weeks as roots develop. Green shoots will also start to grow.
Once the shoots grow to around an inch, start to slowly increase light and warmth. Water to keep the soil lightly moist but never waterlogged, and avoid hitting the shoots when watering. Once the plant has buds, move it to a sunny window with bright, indirect light to wait for your flowers to open.
Once the bulbs have finished blooming, cut off the flower stalks but allow the leaves to remain. This will encourage the plants to store energy in their bulbs for next season.
Like most perennial bulbs, hyacinths are best propagated by splitting offset bulbs from the parent plant in the fall. This method can take two or three years before the bulblet grows to a size sufficient to produce large, vibrant flowers. Thus, propagating hyacinths is an activity best practiced by serious enthusiasts.
Here's how to propagate hyacinths by splitting off the offset bulbs:
- After the flowers have faded but before the foliage has begun to turn brown (usually in late summer or fall), dig up a mature hyacinth with a trowel. Make sure to wear gloves when handling hyacinths, as the bulbs have toxins that can cause skin irritation.
- Wash off the soil, and separate the clump into individual bulbs—the parent bulb and bulblets.
- Replant the bulbs immediately into well-draining soil. Mixing in sand or compost is a good idea if your soil is dense. A handful of bone meal or bulb fertilizer is also recommended at planting time.
How to Grow Hyacinth From Seed
While hyacinths can be propagated from seed, it can take several years to coax the seed into creating a bulb and to nurture the bulb into a sizable structure that will produce a flowering plant.
First, you’ll have to allow your hyacinth blooms to remain on the plant to form seed pods. These pods will ripen from green to tan as they form small black seeds inside. The pods will dry and split open; you can catch the seeds by putting a white sheet under the plant or wrapping pantyhose around the flowers themselves.
Separate out the seeds, and soak them in warm water for one to two days. Then, place them between two moist paper towels in a plastic bag, and put them in the refrigerator to sprout. Once they’ve sprouted, slightly press them into a seed tray filled with moist seed-starting mix, and place them in a cold frame or greenhouse to continue growing.
Potting and Repotting Hyacinth
When planting in pots, either plastic or clay will do as long as they have good drainage. The container should be roughly 6 inches deep. The width of the container depends on how many bulbs you are planting. Hyacinth bulbs in pots can be spaced more closely than when planting in the ground because the bulbs won't need room to multiply. You can squeeze them in so they are almost touching, but leave room for some soil in between to hold water. Repotting should not be necessary if you have properly spaced your bulbs.
Ordinary commercial potting soil is fine for planting hyacinths in containers, though some people like to blend in a little sand with the potting mix. Keep the potting medium damp but not soaking wet until the bulbs sprout. Then, water whenever the soil dries out. Once the bulbs have sprouted, move them to indirect sunlight. Cool temperatures will keep them in bloom longer.
In colder zones (USDA zones 2 and 3), applying a thick layer of mulch over the bulb bed can allow hyacinth bulbs to survive cold winters. You also can position the bulbs an inch or two deeper at the time of planting to help insulate them. In zones 4 to 8, no winter protection should be necessary. However, if your hyacinths are outdoors in containers, cover them or move them to a sheltered spot to prevent the containers from accumulating too much moisture and rotting the bulbs.
If you are growing hyacinths in zone 9 or above, where winter temperatures stay above 60 degrees Fahrenheit, you will need to dig up your bulbs and chill them artificially before replanting. Store them in a mesh bag in a cool, dark spot that remains above freezing but below 45 degrees Fahrenheit for 10 weeks minimum.
Common Pests & Plant Diseases
All kinds of rodents will munch on hyacinth bulbs. You can give them some protection by throwing a handful of gravel into the planting hole, or you can try commercial rodent deterrents. An easier method is to interplant them with daffodils, which rodents tend to avoid.
Few plant diseases affect hyacinth, but the bulbs can rot when planted in dense soil that doesn't drain well.
How to Get Hyacinth to Bloom
Hyacinth bulbs are generally low-maintenance and bloom quite easily on their own in the spring. That being said, you can give yours a leg up by cutting down the flower stalk when this year's blooms fade. Then, when its leaves turn yellow, cut them away as well. Feed them once they bloom, and again in August, to give them a boost for the following spring.
But be aware that most gardeners find it necessary to replant hyacinths (or lift and divide them) every two or three years to keep them blooming robustly. Like many hybrid bulbs, hyacinths lose their vigor rather quickly.
Common Problems With Hyacinth
The hyacinth is a reliable plant that will give you several years of aromatic blooms, but occasionally there are unfortunate issues.
If you've had a late frost after the foliage has appeared, hyacinth leaves can develop disfiguring spots. Sadly, there is not much you can do about it, but in some cases it will not affect the flower stalks that later appear.
Broken, Streaked Petals
Broken and streaked petals can be caused by mosaic virus, which also can cause mottled leaves. Infected plants will need to be dug up and thrown away. Sterilize any tools you use to do this; they, too, can spread the disease.
It is normal for hyacinths to bloom less robustly with every subsequent season. You can prolong their lifespan by regular feeding. Propagating new plants by dividing mature hyacinths can keep you in blooming plants almost indefinitely.
How long do hyacinth live?
Unfortunately, hyacinth bulbs are short-lived and will probably last only three or four years. Many people treat them as annuals and replace them yearly due to decline. This is also a normal growing method in warm-winter zones for gardeners who don't wish to dig up and chill the bulbs.
What's the difference between hyacinth and grape hyacinth?
Hyacinth (Hyacinthus orientalis) and grape hyacinth (Muscari armeniacum) look like similar plants, but they are different species. Hyacinth has large, spiky petals while grape hyacinth's are smaller with bell-shaped flowers. Grape hyacinths are often naturalized in lawns or planted in large drifts—not a common method for standard hyacinths. Grape hyacinths are dark purple-blue without the wide range of colors available with standard hyacinths.
Do squirrels, rabbits, and other creatures dig up hyacinths?
To most rodents, hyacinths are less tasty than many other bulbs, especially tulips. But hungry rabbits will certainly dig up and eat hyacinth bulbs. There are other bulbs, however, that are quite unpalatable, and planting your hyacinths among daffodils, Siberian squill, or grape hyacinths can keep hungry digging rodents at bay.
Can you grow hyacinths indoors?
If you are potting hyacinth indoors for forcing early blooms, you will either need to purchase pre-chilled bulbs or pre-chill them yourself in a refrigerator or other cold location. They can then be nestled in gravel or placed into bulb forcing jars until they bloom. After blooming, indoor hyacinth bulbs are usually discarded. But they are not a good choice for indoor growing if you have pets that nibble on leaves or dig up bulbs.
Toxic Plants. University of California.
How Can I Keep Wildlife From Eating My New Bulbs? University of New Hampshire Cooperative Extension.