One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of making a decision about when it's possible to plant delphinium is to consult the USDA zone info for York.

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 York 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 fully mature. You can get started a little bit earlier by starting your delphinium indoors.

Last Frost Date

On average the last frost is on April 15 in York. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for York is not always accurate the actual date of last frost will vary from year to year. Half of the time in York last frost occurs after April 15 so always be ready to cover your delphinium if you have one of those late frosts.

USDA Zone Info for York

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in York

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