Guide to Refrigerating Tulips, Iris, Hyacinth and Crocus for winter indoor flowering
Step 1. Purchase premium bulbs in February. Early varieties suit this purpose better. Ask your supplier for advice in making your selection.
Step 2. At the beginning of March, place the bulbs in an ‘open’ container or tray, laid only one layer thick. Put the container or tray into the fridge (not freezer) for 6-9 weeks. If cooling Tulips, do not use a fridge that contains fruit or vegetables. The ethylene gas produced by fruit and vegetables will kill the flower buds inside the Tulips. Consider using a bar fridge that contains only drinks. The temperature of the fridge should be between 2 and 5 degrees Celsius. This temperature is standard for most fridges.
Step 3. Open the fridge once every few days for about 30 seconds to a minute. This is to allow fresh air around the bulbs.
Step 4. After 6 weeks of refrigeration in cool winter climates or 9 weeks in warm winter climates, remove the bulbs from the fridge and commence to pot them up. Use a quality Australian standards potting mix and select a well drained pot. Mix some slow release fertilizer through your potting mix if not already done by the manufacturer. Plant the bulbs so they are covered by 2.5-3cm of soil above their tips. Allow for the potting mix to settle after it is watered so have a bit more mix above the bulbs to allow for this. Remember, bulbs don’t mind being a bit crowded and a full pot will look best. Water the pot well after planting.
Step 5. Place the planted pot in a cool shaded spot until shoots 2-3cm long appear above the soil.
Note: It is important that the pot remain cool and damp whilst the roots and shoots develop.
Step 6. Move the pot with 2-3cm shoots to a bright location indoors. The bulbs will now continue to grow and flower inside your home.
Tips: Do not place the pot near a heater. Water as necessary. Soil should remain damp under the surface.
Please note: Only new bulbs should be forced. Once bulbs have been treated in this way they should be grown normally in the garden for at least 2 years to rebuild their strength and vigour before attempting to reforce them.
Keep lids open or removed from containers at all times. Bulbs
should only be one layer deep.
Only aerated plastic bags like those used by Garden Express should be used for bulb storage.
Never place bulbs with ripening fruit. The gases produced may kill flower buds.
Never store bulbs in sealed containers.