The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to figure out when it's possible to plant nierembergia by reviewing the USDA zone info for Richmond Hill.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's a bad idea to plant nierembergia until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant nierembergia in Richmond Hill is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant nierembergia and expect a good harvest is probably August. Any later than that and your nierembergia may not have a chance to fully mature. You can get started a few weeks earlier by starting your nierembergia indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Richmond Hill. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Richmond Hill may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Richmond Hill it frosts late in the year after March 15 be ready to cover your nierembergia if you have one of those late frosts.

USDA Zone Info for Richmond Hill

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Richmond Hill

You may be interested in your other planting guides for Richmond Hill.