When to Plant Delphinium in Slidell, LA

The USDA Zone info is a great tool for gardeners to help us estimate 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 a good idea to figure out when it's a good idea to plant delphinium by reviewing the USDA zone info for Slidell.


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.

Since delphinium are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than more sensitive plants.

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 Slidell is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant delphinium and expect a good harvest is probably September. If you wait any later than that and your delphinium may not have a chance to grow to maturity. If you are starting your delphinium indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on February 15 in Slidell. You can expect an average low temperature of 20°F in the coldest months of winter.

Remember that USDA zone info for Slidell is an average and the actual date of last frost will vary from year to year. Half of the time in Slidell it frosts late in the year after February 15 so be sure to be ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Slidell

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low20°F
Highest Expected Low25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Slidell

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