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.

By reviewing the USDA zone info for Thornton you will be able to determine when it's the best time to plant tritoma.

Planting Calendar for Tritoma

Frost tolerance for tritoma:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Tritoma do well in cold which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant tritoma in Thornton 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 tritoma and expect a good harvest is probably September. Any later than that and your tritoma may not have a chance to grow to maturity. Starting your tritoma indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Thornton. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Thornton and it changes from year to year. Half of the time in Thornton you get a frost after April 15 so always be ready to cover your tritoma if you have 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.