One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

It's possible to determine when it's the best time to plant california poppy by looking at the USDA zone info for Zone 4b.

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.

You can plant california poppy a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant california poppy in Zone 4b 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 california poppy and expect a good harvest is probably August. Any later than that and your california poppy may not have a chance to fully mature. Starting your california poppy indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Zone 4b the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that USDA zone info for Zone 4b is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Zone 4b there is a last frost after May 15 be ready to cover your california poppy in the event of a surprise late frost.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.