Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when you can plant leeks by looking at the USDA zone info for Castle Rock.

Planting Calendar for Leeks

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

You can plant leeks quite a bit earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant leeks in Castle Rock 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 leeks and expect a good harvest is probably September. Any later than that and your leeks may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your leeks indoors.

Last Frost Date

In Castle Rock 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.

Always keep in mind that USDA zone info for Castle Rock may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Castle Rock you get surprised by a frost after April 15 so just be sure to be ready to cover your leeks in the event of one of those late frosts.

USDA Zone Info for Castle Rock

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 Castle Rock

You may be interested in your other planting guides for Castle Rock.