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.

The earliest that you can plant marigold in Corvallis should be estimated by referring to the USDA zone info.

Planting Calendar for Marigold

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

Marigold do not do well in cold weather which tells us that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant marigold in Corvallis 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 marigold and expect a good harvest is probably August. Any later than that and your marigold may not have a chance to fully mature. You can get started a little bit earlier by starting your marigold indoors.

Last Frost Date

The average date of last frost is March 15 in Corvallis. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Corvallis may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Corvallis you get a frost after March 15 be ready to protect your marigold in the event of one of those late frosts.

USDA Zone Info for Corvallis

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 Corvallis

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