One of the first steps you take when you are estimating 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.

It's possible to determine when it's possible to plant delphinium by looking at the USDA zone info for Trinity.

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 are barely cold tolerant which means that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant delphinium in Trinity 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. You probably don't want to wait any later than that or else your delphinium may not have a chance to really do well. You can get started a couple of weeks earlier by starting your delphinium indoors.

Last Frost Date

The average date of last frost is April 15 in Trinity. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Trinity is not always accurate the actual date of last frost is different every year. Half of the time in Trinity you get surprised by a frost after April 15 so make sure that you are ready to protect your delphinium if you have a late frost.

USDA Zone Info for Trinity

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Trinity

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