When to Plant Hypericum in Denison, IA

One of the first steps you take when you are determining 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.

The earliest that you can plant hypericum in Denison should be figured out by referring to the USDA zone info.


Planting Calendar for Hypericum

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

Since hypericum do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

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

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

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Denison. 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 Denison is just an average and the actual date of last frost is different every year. Since half of the time in Denison you get a frost after April 15 be ready to protect your hypericum in the event of a surprise late frost.

USDA Zone Info for Denison

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 Denison

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