But if you wait too long to get the bulbs you get bulbs that are picked over and/or damaged by the stores conditions. And if you plant your bulbs too early, the bulbs start to sprout.
Buy the bulbs…store them in COOL dry place until it is time to plant them. Examples of a cool dry place include garages, basements and cold cellars.
When is the right time to plant spring-blooming bulbs?
The Bulb Society has rough estimates when you should plant in your bulbs in each USDA Plant Hardiness Zone:
Zone 1 by early September
Zone 2 by early September
Zone 3 September
Zone 4 by late September to early October
Zone 5 by late September to early October
Zone 6 by mid-October
Zone 7 by early November
Zone 8 by early November
Zone 9 by early December (some chilling required)
Zone 10 by early December (some chilling required)
Remember there are seasonal variations. I am in Zone 5…according to the chart I could plant bulbs now, but it has been a warm September this year. It might be too warm still and the bulbs will start to sprout.
So, how do I know for sure, when it is the right time to plant spring-blooming bulbs?
The best solution is to measure the soil temperature…
Plant the bulbs when the soil is consistently below 15 degrees Celsius (60 degrees Fahrenheit). Measuring the soil temperature with an oven thermometer is easy. But again, I know that there are gardeners who either don’t like to measure or don’t have a thermometer. The next best way is to plant bulbs when the night temperatures are consistently in the range of 4 to 8 degrees Celsius (about 40 to 45 degrees Fahrenheit).
When I checked the soil temperature today (September 30), it was still 19 degrees Celsius (66 degrees Fahrenheit). Still too warm! Great, I still have time to buy my bulbs…