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When to Plant Helianthemum in Newton, IA

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

You can estimate when it's the best time to plant helianthemum in Newton by using the USDA zone info.


Planting Calendar for Helianthemum

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

Helianthemum are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than plants that are more sensitive to the cold.

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

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

Last Frost Date

The average date of last frost is April 15 in Newton. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Newton and it changes from year to year. Since half of the time in Newton last frost occurs after April 15 be ready to protect your helianthemum if you have one of those late frosts.

USDA Zone Info for Newton

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 Newton

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