When to Plant California Poppy in Oswego, IL

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Oswego should be read to estimate when it's possible to plant california poppy.


Planting Calendar for California Poppy

Frost tolerance for california poppy: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since california poppy are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant california poppy in Oswego is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant california poppy and expect a good harvest is probably August. You probably don't want to wait any later than that or else your california poppy may not have a chance to really do well. Starting your california poppy indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Oswego. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Oswego is not always accurate the actual date of last frost changes from year to year. Since half of the time in Oswego you get a frost after April 15 be ready to cover your california poppy in the event of one of those late frosts.

USDA Zone Info for Oswego

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°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 -10°F.

Plants to Grow in Oswego

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