One of the first steps you take when you are making a decision about 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.

In New Castle you can estimate when you can plant dahlia by referring to the USDA zone info.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You should not plant dahlia until after the last frost because they do not do well in cold weather.

The earliest that you can plant dahlia 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 dahlia and expect a good harvest is probably August. Any later than that and your dahlia may not have a chance to grow to maturity. If you are starting your dahlia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in New Castle. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for New Castle may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in New Castle last frost occurs after April 15 so be sure to be ready to protect your dahlia in the event of one of those late frosts.

USDA Zone Info for New Castle

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 New Castle

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