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.

In Thornton you can estimate when it's the best time to plant bleeding hearts by checking out the USDA zone info.

Planting Calendar for Bleeding Hearts

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

Bleeding Hearts do ok in moderate cold which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant bleeding hearts in Thornton 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 bleeding hearts and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bleeding hearts may not have a chance to grow to maturity. You can get started a little bit earlier by starting your bleeding hearts indoors.

Last Frost Date

In Thornton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Thornton is an average the actual date of last frost will vary from year to year. Since half of the time in Thornton you get surprised by a frost after April 15 be ready to protect your bleeding hearts in the event of one of those late frosts.

USDA Zone Info for Thornton

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 Thornton

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