When to Plant Sunflowers in Monmouth, OR

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Monmouth it's possible to determine when it's possible 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 do not do well in cold weather you must wait until after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant sunflowers
Possibly ok, but a risky time to plant sunflowers
Probably not a good time to plant sunflowers

The earliest that you can plant sunflowers in Monmouth 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. 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

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

Always keep in mind that USDA zone info for Monmouth may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Monmouth last frost occurs after March 15 so always be ready to protect your sunflowers if you have a surprise late frost.

USDA Zone Info for Monmouth

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 Low15°F
Highest Expected Low20°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 Monmouth

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