One of the best tools that you have as gardeners to help us determine 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.

It's a good idea to figure out when it's the best time to plant saxifraga by using the USDA zone info for Gaithersburg.

Planting Calendar for Saxifraga

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

Since saxifraga do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant saxifraga in Gaithersburg 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 saxifraga and expect a good harvest is probably August. Any later than that and your saxifraga may not have a chance to really do well. You can get started a few weeks earlier by starting your saxifraga indoors.

Last Frost Date

On average the last frost is on April 15 in Gaithersburg. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Gaithersburg may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Gaithersburg it frosts late in the year after April 15 so make sure that you are prepared to protect your saxifraga if you have a surprise late frost.

USDA Zone Info for Gaithersburg

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Gaithersburg

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