When to Plant Delphinium in Belvidere, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant delphinium in Belvidere should be determined by checking out the USDA zone info.


Planting Calendar for Delphinium

Frost tolerance for delphinium: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Delphinium can survive in a tiny bit of cold which means that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant delphinium
Possibly ok, but a risky time to plant delphinium
Probably not a good time to plant delphinium

The earliest that you can plant delphinium in Belvidere is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant delphinium and expect a good harvest is probably August. Any later than that and your delphinium may not have a chance to fully mature. You can get started a few weeks earlier by starting your delphinium indoors.

Last Frost Date

The average date of last frost is April 15 in Belvidere. In the coldest months of winter you should expect an average low temperature of -15°F.

Always keep in mind that USDA zone info for Belvidere may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Belvidere there is a last frost after April 15 so make sure that you are ready to protect your delphinium in the event of a surprise late frost.

USDA Zone Info for Belvidere

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Belvidere

You may be interested in your other planting guides for Belvidere.