One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Altoona you can estimate when you can plant thunbergia by referring to the USDA zone info.

Planting Calendar for Thunbergia

Frost tolerance for thunbergia:	Not tolerant of frost.
When to plant:	After the last frost.

Thunbergia require warm weather which means that you must wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant thunbergia in Altoona is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

In Altoona 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.

Always keep in mind that USDA zone info for Altoona is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Altoona you get surprised by a frost after April 15 so always be ready to protect your thunbergia in the event of one of those late frosts.

USDA Zone Info for Altoona

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 Altoona

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