What is the traditional approach to planting bulbs?

Question

I wandered onto this page about how to plant bulbs indoors. It mentioned that we need to place the bulb in the soil and put it in a cool, dark place for the root system to develop, which takes about 6 weeks. This is different from what we do here. I don't know what temperature range they're referring to when they say "cool".

Here in Hong Kong the weather is quite warm even in Winter (15+ degree Celsius , so what we do is place the bulb without soil in the fridge for 6 weeks. After that, we put them in the soil and let them grow. Are both ways correct? How do you define "cool"?

Answer 1

The cooling period depends on if we're talking "hardy" bulbs or "tender" bulbs (or "semi-tender" bulbs).

Hardy bulbs require a cooling period of 40°F (4°C) or below. Most can withstand weeks of sub-freezing temperatures.

• Crocuses, Daffodils, Scilla, Tulips, etc can all be left in the ground here (USDA Hardiness Zone 6a) and we get below 0°F (-18°C) every year for at least a few days (if not 2 to 3 weeks).

Tender bulbs require a cooling period of 50 to 60°F (10 to 16°C).

Semi-tender bulbs require a cooling period that falls somewhere inbetween, though they can take "light" freezing temperatures, but not for prolonged periods of time.

Exactly how the bulb gets it required cooling period really doesn't mater (as far as I'm aware), the important thing is, it gets that cooling period...