When to Plant Astilbe in Newton, IA

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

The earliest that you can plant astilbe in Newton should be figured out by checking out the USDA zone info.


Planting Calendar for Astilbe

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

Astilbe do ok in mild cold which means that you can plant them slightly earlier in the year than other plants that might not handle the cold.

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

The earliest that you can plant astilbe in Newton 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 astilbe and expect a good harvest is probably August. Any later than that and your astilbe may not have a chance to really do well. You can get started a couple of weeks earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost is on April 15 in Newton. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Newton and it is different every year. Since half of the time in Newton it frosts late in the year after April 15 be ready to protect your astilbe if you have a late frost.

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.