When to Plant Delphinium in Trinidad, CO

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's possible to plant delphinium by looking at the USDA zone info for Trinidad.


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 get them planted just a bit earlier than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant delphinium
Possibly ok, but a risky time to plant delphinium
Probably not a good time to plant delphinium

The earliest that you can plant delphinium in Trinidad 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. If you are starting your delphinium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Trinidad the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Trinidad is an average and the actual date of last frost changes from year to year. Half of the time in Trinidad last frost occurs after April 15 so make sure that you are ready to cover your delphinium in the event of one of those late frosts.

USDA Zone Info for Trinidad

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Trinidad

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