One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Liberty Lake you should be able to figure out when it's a good idea to plant sunflowers.

Planting Calendar for Sunflowers

Frost tolerance for sunflowers:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since sunflowers require warm weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant sunflowers in Liberty Lake 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. Any later than that and your sunflowers may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

The average date of last frost is April 15 in Liberty Lake. In the coldest months of winter you should expect an average low temperature of -5°F.

Just be sure to remember that USDA zone info for Liberty Lake is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Liberty Lake it frosts late in the year after April 15 so always be ready to cover your sunflowers if you have a surprise late frost.

USDA Zone Info for Liberty Lake

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Liberty Lake

You may be interested in your other planting guides for Liberty Lake.