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When to Plant Scarlet Pimpernels in Knoxville, IA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's the best time to plant scarlet pimpernels is to examine the USDA zone info for Knoxville.


Planting Calendar for Scarlet Pimpernels

Frost tolerance for scarlet pimpernels: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since scarlet pimpernels are barely cold tolerant 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 scarlet pimpernels
Possibly ok, but a risky time to plant scarlet pimpernels
Probably not a good time to plant scarlet pimpernels

The earliest that you can plant scarlet pimpernels 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 scarlet pimpernels and expect a good harvest is probably August. If you wait any later than that and your scarlet pimpernels may not have a chance to grow to maturity. Starting your scarlet pimpernels indoors is a great way to get them started 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 can change quite a bit from year to year. Half of the time in Knoxville you get surprised by a frost after April 15 so just be sure to be ready to protect your scarlet pimpernels 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.