When to Plant Angel's Trumpets in Knoxville, IA

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

The USDA zone info for Knoxville can be used to determine when it's possible to plant angel's trumpets.


Planting Calendar for Angel's Trumpets

Frost tolerance for angel's trumpets: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since angel's trumpets do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant angel's trumpets
Possibly ok, but a risky time to plant angel's trumpets
Probably not a good time to plant angel's trumpets

The earliest that you can plant angel's trumpets in Knoxville 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 angel's trumpets and expect a good harvest is probably August. Any later than that and your angel's trumpets may not have a chance to grow to maturity. Starting your angel's trumpets indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Knoxville and it can change quite a bit from year to year. Since half of the time in Knoxville last frost occurs after April 15 be ready to cover your angel's trumpets in the event of a surprise late frost.

USDA Zone Info for Knoxville

Here is the info for USDA Zone 5b.

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

Plants to Grow in Knoxville

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