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.

By checking out the USDA zone info for Monrovia it's possible to determine when to plant datura.

Planting Calendar for Datura

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

Datura do well in very little cold which tells us that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant datura in Monrovia 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 datura and expect a good harvest is probably September. If you wait any later than that and your datura may not have a chance to really do well. If you are starting your datura indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in Monrovia. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Monrovia is an average the actual date of last frost is different every year. Since half of the time in Monrovia you get surprised by a frost after January 31 be ready to protect your datura in the event of one of those late frosts.

USDA Zone Info for Monrovia

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Monrovia

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