One of the first steps you take when you are making a decision about 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.

The first chance to plant california poppy in Willowbrook can be estimated by referring to the USDA zone info.

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 do ok in moderate cold you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant california poppy in Willowbrook 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 grow to maturity. If you are starting your california poppy indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Willowbrook. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember 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 Willowbrook and it changes from year to year. Half of the time in Willowbrook there is a last frost after April 15 so make sure that you are prepared to cover your california poppy in the event of a surprise late frost.

USDA Zone Info for Willowbrook

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 Willowbrook

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