The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant delphinium in North Royalton can be estimated by referring to the USDA zone info.

Planting Calendar for Delphinium

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

You can plant delphinium slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant delphinium in North Royalton 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 delphinium and expect a good harvest is probably August. If you wait any later than that and your delphinium may not have a chance to grow to maturity. If you are starting your delphinium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for North Royalton and it will vary from year to year. Since half of the time in North Royalton last frost occurs after April 15 be ready to cover your delphinium if you have a surprise late frost.

USDA Zone Info for North Royalton

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 North Royalton

You may be interested in your other planting guides for North Royalton.