One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when it's possible to plant stocks is to look at the USDA zone info for Thornton.

Planting Calendar for Stocks

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

Since stocks are barely cold tolerant you can plant them slightly earlier in the year than more sensitive plants.

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

Last Frost Date

In Thornton the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Thornton is just an average the actual date of last frost changes from year to year. Since half of the time in Thornton it frosts late in the year after April 15 be ready to cover your stocks if you have a surprise late frost.

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.