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.

The USDA zone info for Mckinney can be used to estimate when to plant helianthemum.

Planting Calendar for Helianthemum

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

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

The earliest that you can plant helianthemum in Mckinney 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 helianthemum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your helianthemum may not have a chance to really do well. If you are starting your helianthemum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Mckinney. You can expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Mckinney is not always accurate the actual date of last frost is different every year. Half of the time in Mckinney you get a frost after March 15 so just be sure to be ready to protect your helianthemum in the event of a late frost.

USDA Zone Info for Mckinney

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Mckinney

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