When to Plant Tall Phlox in Red Oak, 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.

In Red Oak you can estimate when it's a good idea to plant tall phlox by looking at the USDA zone info.


Planting Calendar for Tall Phlox

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

You can plant tall phlox a little earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

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

Last Frost Date

In Red Oak the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Red Oak is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Red Oak you get a frost after April 15 be ready to protect your tall phlox if you have one of those late frosts.

USDA Zone Info for Red Oak

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 Red Oak

You may be interested in your other planting guides for Red Oak.