Growing spring bulbs indoors lets you enjoy the colours and fragrance of spring while it’s still months away, plus it’s a great idea if you’re lacking garden space. The key to success with indoor bulbs is to plan ahead. As you’re not planting the bulbs outdoors, you need to mimic “Winter.” This is necessary for them to flower, as they need a period of coldness to grow and bloom. Getting bulbs to bloom in Winter is called ‘forcing’ but it’s not as unkind as it sounds. You’re simply tricking the bulb in to thinking that Spring has come earlier than it actually has. In essence, you’re replicating the conditions of the cold season your bulbs would experience if you had planted them outdoors.
Grow Spring Bulbs Indoors
Daffodils, paperwhites and hyacinths make excellent candidates for growing indoors. However, just about any hardy bulb, and even a few tender bulbs, can be forced to bloom through the winter. Healthy bulbs should be plump, firm and unblemished. Before buying, inspect them carefully.
Step 2: Pick a container
You can plant your bulbs in pots or containers filled with potting soil or gravel. Things like old tea cups, buckets, utensil caddies, shallow dishes, ornamental pots, flower vases, bulb vases, and water pitchers are a few artistic selections you can choose from.
Step 3: Planting time
It is recommended that you plant in a container that has drainage holes, however, you can pop a layer of stones or pebbles on the bottom of your chosen container to aid with drainage. Add a layer of potting mix and gently place your bulbs in the soil with the pointy tip facing upwards. Fill the pot with soil and add bulbs at the right depth depending on the bulb type. When planting your bulbs, place them no more than 3cm away from one another (but never touching to avoid inadvertently causing rot), and plant as many as you can in each container for a ‘wow’ factor once they bloom. Water well after planting.
Once planted, it is time to give the bulbs the cold temperature treatment. If you have a cold shed, garage or basement you can pop your bulbs in there, otherwise you can opt for the fridge. In the refrigerator, cover the pots with plastic bags that have had a few breathing holes punched in them. Do not allow the bulbs to freeze as they will die and ultimately rot. The bulbs will not grow properly if it is either too cold or too hot.
Note: if you don’t have a cool space other than the refrigerator and don’t want your potted containers to take up all your fridge space, you can chill the bulbs before planting.
Check on the bulbs now and again while they are in hiding. Keep the soil moist, but do not over water at this time.
Step 4: Removing from the cold
Bulbs need up to 12 weeks in the cold, paperwhites should emerge after 6-10 weeks, hyacinths around 8-10 weeks. When you remove your bulbs from their cold treatment, the change in temperature that they experience will signal (force) the bulbs to produce flower stalks, just as they would do in spring time. Place your pot or container in a sunny spot like a window sill. Your bulbs should flower in around 3-4 weeks. The closer to spring time, the more rapidly the flowers will grow. Once the bulbs are blooming, move the pots to a cool location each night to prolong the bloom time.
Flowering takes a considerable amount of the bulb’s stored energy. Therefore, bulbs that have been forced to bloom are unlikely to bloom well again. Compost the forced bulbs after blooming.