One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Madisonville you can estimate when it's the best time to plant delphinium by referring to the USDA zone info.

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 barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Madisonville 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 grow to maturity. If you are starting your delphinium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Madisonville. You can expect an average low temperature of 15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Madisonville and it will vary from year to year. Half of the time in Madisonville last frost occurs after March 15 so make sure that you are ready to protect your delphinium in the event of one of those late frosts.

USDA Zone Info for Madisonville

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Madisonville

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