One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Zone 4a you should be able to estimate when to plant scabiosa.

Planting Calendar for Scabiosa

Frost tolerance for scabiosa:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant scabiosa just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant scabiosa in Zone 4a 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 scabiosa and expect a good harvest is probably August. Any later than that and your scabiosa may not have a chance to fully mature. You can get started a few weeks earlier by starting your scabiosa indoors.

Last Frost Date

The average date of last frost is May 15 in Zone 4a. In the coldest months of winter you can expect an average low temperature of -30°F.

Remember that USDA zone info for Zone 4a is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 4a you get a frost after May 15 so just be sure to be ready to cover your scabiosa in the event of a surprise late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in your other planting guides for Zone 4a.