When to Plant Lettuce in Knoxville, IA

One of the first steps you take when you are figuring out 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.

You should be able to figure out when it's the best time to plant lettuce by looking at the USDA zone info for Knoxville.


Planting Calendar for Lettuce

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

Lettuce tend to make it in moderate cold which means that you can plant them a little earlier in the year than other plants that might not handle the cold.

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

The earliest that you can plant lettuce in Knoxville 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 lettuce and expect a good harvest is probably September. If you wait any later than that and your lettuce may not have a chance to grow to maturity. If you are starting your lettuce 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.

It's important to remember that USDA zone info for Knoxville is not always accurate and the actual date of last frost is different every year. Since half of the time in Knoxville it frosts late in the year after April 15 be ready to protect your lettuce 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.