The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Prosper you should be able to determine when it's a good idea to plant sweet williams.

Planting Calendar for Sweet Williams

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

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

The earliest that you can plant sweet williams in Prosper is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant sweet williams and expect a good harvest is probably September. If you wait any later than that and your sweet williams may not have a chance to grow to maturity. Starting your sweet williams indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Prosper. You should expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Prosper is just an average the actual date of last frost changes from year to year. Half of the time in Prosper last frost occurs after March 15 so always be ready to cover your sweet williams if you have a late frost.

USDA Zone Info for Prosper

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Prosper

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