One of the best tools that you have as gardeners to help us determine 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.

You can estimate when it's a good idea to plant oriental poppies in Denver by checking out the USDA zone info.

Planting Calendar for Oriental poppies

Frost tolerance for oriental poppies:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Oriental poppies are moderately cold tolerant which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant oriental poppies in Denver is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant oriental poppies and expect a good harvest is probably September. You probably don't want to wait any later than that or else your oriental poppies may not have a chance to fully mature. If you are starting your oriental poppies indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Denver the average date of last frost happens on April 15. 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 Denver is just an average and the actual date of last frost is different every year. Since half of the time in Denver it frosts late in the year after April 15 be ready to protect your oriental poppies if you have one of those late frosts.

USDA Zone Info for Denver

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 Denver

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