The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to figure out when it's possible to plant tall phlox by referring to the USDA zone info for Olathe.

Planting Calendar for Tall Phlox

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

Tall Phlox can survive in some cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant tall phlox in Olathe 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. Any later than that and your tall phlox may not have a chance to fully mature. If you are starting your tall phlox indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Olathe. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Olathe may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Olathe it frosts late in the year after April 15 so always be ready to cover your tall phlox if you have one of those late frosts.

USDA Zone Info for Olathe

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Olathe

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