One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Royal Oak it's a good idea to figure out when it's the best time to plant nierembergia.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After the last frost.

Since nierembergia are not cold tolerant you have to wait until after the last frost before you can plant them.

The earliest that you can plant nierembergia in Royal Oak 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. You probably don't want to wait any later than that or else your nierembergia may not have a chance to really do well. If you are starting your nierembergia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Royal Oak the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Royal Oak and it is different every year. Half of the time in Royal Oak last frost occurs after April 15 so just be sure to be ready to protect your nierembergia if you have one of those late frosts.

USDA Zone Info for Royal Oak

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Royal Oak

You may be interested in your other planting guides for Royal Oak.