When to Plant Geranium in Knoxville, IA

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Knoxville it's possible to determine when to plant geranium.


Planting Calendar for Geranium

Frost tolerance for geranium: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

You should not plant geranium until after the last frost when the weather gets warmer because they require warm weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant geranium
Possibly ok, but a risky time to plant geranium
Probably not a good time to plant geranium

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

Last Frost Date

In Knoxville the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Knoxville may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Knoxville last frost occurs after April 15 so always be ready to cover your geranium in the event of a 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.