One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 tall phlox in Montevideo should be determined by referring to 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.

Tall Phlox do ok in a little bit of 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 Montevideo 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 tall phlox and expect a good harvest is probably August. 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 May 15 in Montevideo. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Montevideo is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Montevideo you get a frost after May 15 be ready to cover your tall phlox in the event of a late frost.

USDA Zone Info for Montevideo

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Montevideo

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