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When to Plant Gomphrena in Johnston, IA

One of the best tools that you have as gardeners to help us figure out 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.

A common way of getting a good idea when it's possible to plant gomphrena is to check out the USDA zone info for Johnston.

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Planting Calendar for Gomphrena

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

Gomphrena do well in mild cold which tells us that 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 gomphrena
Possibly ok, but a risky time to plant gomphrena
Probably not a good time to plant gomphrena

The earliest that you can plant gomphrena in Johnston 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 gomphrena and expect a good harvest is probably August. You probably don't want to wait any later than that or else your gomphrena may not have a chance to really do well. If you are starting your gomphrena indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Johnston the average date of last frost happens on April 15. You can expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Johnston may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Johnston you get a frost after April 15 be ready to cover your gomphrena if you have a surprise late frost.

USDA Zone Info for Johnston

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Johnston

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