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

You can figure out when it's a good idea to plant monarda in San Juan by checking out the USDA zone info.

Planting Calendar for Monarda

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

You can plant monarda slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant monarda in San Juan 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 monarda and expect a good harvest is probably September. If you wait any later than that and your monarda may not have a chance to fully mature. You can get started a few weeks earlier by starting your monarda indoors.

Last Frost Date

On average the last frost is on February 15 in San Juan. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for San Juan may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in San Juan it frosts late in the year after February 15 be ready to cover your monarda in the event of a surprise late frost.

USDA Zone Info for San Juan

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in San Juan

You may be interested in your other planting guides for San Juan.