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.

The USDA zone info for Mount Vernon should be reffered to in order to estimate when it's the best time to plant calibrachoa.

Planting Calendar for Calibrachoa

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

Since calibrachoa do ok in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant calibrachoa in Mount Vernon 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 calibrachoa and expect a good harvest is probably August. You probably don't want to wait any later than that or else your calibrachoa may not have a chance to grow to maturity. Starting your calibrachoa indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Remember that USDA zone info for Mount Vernon may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Mount Vernon there is a last frost after April 15 so make sure that you are prepared to cover your calibrachoa if you have one of those late frosts.

USDA Zone Info for Mount Vernon

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 Mount Vernon

You may be interested in your other planting guides for Mount Vernon.