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

A common way of determining when it's the best time to plant sunflowers is to check out the USDA zone info for Forest Grove.

Planting Calendar for Sunflowers

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

Since sunflowers are not cold tolerant you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant sunflowers in Forest Grove 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. If you wait any later than that and your sunflowers may not have a chance to grow to maturity. Starting your sunflowers 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 Forest Grove. In the coldest months of winter you should expect an average low temperature of 15°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Forest Grove and it changes from year to year. Half of the time in Forest Grove it frosts late in the year after March 15 so be sure to be ready to cover your sunflowers in the event of a late frost.

USDA Zone Info for Forest Grove

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Forest Grove

You may be interested in your other planting guides for Forest Grove.