How to Force Bulbs for Beautiful Winter Blooms Indoors, According to Flower Experts

If you want to enjoy the vibrant colors and fragrances of flowers indoors while it's bleak and chilly outside, consider forcing bulbs. Tulips, daffodils, hyacinths, crocuses, and other spring-flowering bulbs can be forced indoors, allowing you to see spring blooms even in the colder months.

Although forcing bulbs may seem complicated, it's a simple gardening technique. This method tricks the bulb into blooming out of season by simulating the winter conditions, followed by the warmth and light it would receive in spring.

Forcing bulbs to bloom early is simple and requires minimal materials. In this guide, our gardening experts provide easy-to-follow instructions for getting your bulbs to produce spring blooms even in the middle of winter.

What It Means to Force Bulbs

Forcing bulbs is the practice of encouraging them to bloom outside their natural growing season, allowing gardeners to enjoy their beauty during winter. "By skillfully replicating the cycle of the seasons, we invite these blooms to brighten the quietest days of the year," says John Leader, floriculture manager at Longwood Gardens. Bulbs can either be forced in water or soil to speed up their development, resulting in beautiful indoor blooms during the dreary cold months.

Types of Bulbs You Can Force

While not all bulbs can be forced, tulips, daffodils, hyacinths, and crocuses lend themselves beautifully to forcing, offering an array of colors and fragrances. "Hippeastrum, commonly called amaryllis, and paperwhite narcissus are also popular choices, requiring little preparation to grace your home with their elegant blooms," says Leader. 

When to Chill Bulbs

All bulbs, except paperwhites and amaryllis, need a cold period to bloom. “Chilling bulbs mimics the cool of winter, signaling the dormant bulb to prepare for growth. This essential step ensures a strong, healthy bloom that will brighten your indoor space during winter,” says Leader. Although each bulb has different chilling requirements, these general guidelines will simulate winter conditions for your bulbs, resulting in abundant future blooms.

• Chill in September, bloom in January
• Chill in October, bloom in February
• Chill in November, bloom in March
• Chill in December, bloom in April

Bulb Name	Chill Time
Tulips	10 to 16 weeks
Daffodils	2 to 3 weeks
Snowdrop	15 weeks
Hyacinth	12 to 15 weeks
Iris	13 to 15 weeks
Crocus	8 to 15 weeks

How to Force Bulbs in Soil

The easiest way to force bulbs is to pot them in well-draining soil.  "Before you begin, be sure to pick healthy bulbs free of mold or soft spots," says Emily Scott owner of Scott Farm in Maine.

What You'll Need:

• A garden container
• Potting soil
• Healthy bulbs
• Water

Steps

1. Begin with a container with a drainage hole and fill it halfway with rich potting soil.
2. Arrange the bulbs with their tips up, close but not touching, and cover them with soil, leaving the tips exposed.
3. Water deeply, then place the container in a cool, dark spot (40 degrees Fahrenheit) for the chilling period. A refrigerator, basement, or unheated garage are suitable spots.
4. Once chilled, move the container to a warm, sunlit area, watering as needed to encourage growth.
5. In a few weeks, the bulbs should bloom.

How to Force Bulbs in Water

Even a novice gardener can learn how to force bulbs in water. If you don't have a forcing vase, using pebbles will stabilize the bulb and ensure it doesn't sit directly in the water.

What You’ll Need:

• A forcing vase or mason jar
• Small pebbles or stones
• Healthy bulbs
• Fresh water

Steps

1. Choose a clear vase or mason jar to display both the bulb and roots.
2. Fill the jar partially with pebbles, placing the bulb on top with the pointed end facing up. (If using a forcing vase, fill the vessel with water only just below the bulb).
3. Add water until it is just below the base of the bulb, ensuring that the bulb itself does not sit directly in the water.
4. Adjust the pebbles to help stabilize the bulb and prevent it from tipping over.
5. Place the vase in a paper bag and store it in a cool, dark location, such as the refrigerator.
6. After chilling, move the vase to a bright, warm space and add water as needed. The water should touch the area where the roots are forming.
7. In a few weeks, the bulbs should bloom.