One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of determining when it's the best time to plant sunflowers is to examine the USDA zone info for Manassas.

Planting Calendar for Sunflowers

Frost tolerance for sunflowers:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant sunflowers until after the last frost because they require warm weather.

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

The last month that you can plant sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. If you are starting your sunflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Manassas the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

It's important to remember that USDA zone info for Manassas is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Manassas you get a frost after April 15 be ready to protect your sunflowers if you have one of those late frosts.

USDA Zone Info for Manassas

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Manassas

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