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.

By using the USDA zone info for New Castle it's a good idea to estimate when it's the best time to plant heliotrope.

Planting Calendar for Heliotrope

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

Heliotrope do not do well in cold weather which means that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant heliotrope in New Castle 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 heliotrope and expect a good harvest is probably August. Any later than that and your heliotrope may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your heliotrope indoors.

Last Frost Date

On average the last frost has passed is on April 15 in New Castle. In the coldest months of winter you should expect an average low temperature of 0°F.

Since the USDA zone info for New Castle may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in New Castle it frosts late in the year after April 15 so make sure that you are ready to cover your heliotrope in the event of a surprise late frost.

USDA Zone Info for New Castle

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in New Castle

You may be interested in your other planting guides for New Castle.