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.

In Madisonville you can determine when to plant penstemon by looking at the USDA zone info.

Planting Calendar for Penstemon

Frost tolerance for penstemon:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant penstemon a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant penstemon in Madisonville 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 penstemon and expect a good harvest is probably September. You probably don't want to wait any later than that or else your penstemon may not have a chance to really do well. Starting your penstemon indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Madisonville is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Madisonville you get surprised by a frost after March 15 be ready to cover your penstemon in the event of a late frost.

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.