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.

It's possible to estimate when it's the best time to plant delphinium by referring to the USDA zone info for Roscoe.

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.

Delphinium can survive in some cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant delphinium in Roscoe 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 couple of weeks earlier by starting your delphinium indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Roscoe. You can expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Roscoe is not always accurate and the actual date of last frost is different every year. Half of the time in Roscoe you get a frost after April 15 so make sure that you are prepared to protect your delphinium if you have one of those late frosts.

USDA Zone Info for Roscoe

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 Roscoe

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