One of the first steps you take when you are estimating your gardening schedule is find your 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 tropical water plants in Waltham should be figured out by checking out the USDA zone info.

Planting Calendar for Tropical Water Plants

Frost tolerance for tropical water plants:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant tropical water plants until after the last frost because they are not cold tolerant.

The earliest that you can plant tropical water plants in Waltham is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant tropical water plants and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tropical water plants may not have a chance to grow to maturity. If you are starting your tropical water plants indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Waltham the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Waltham is an average the actual date of last frost will vary from year to year. Half of the time in Waltham there is a last frost after April 15 so make sure that you are ready to protect your tropical water plants in the event of a surprise late frost.

USDA Zone Info for Waltham

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 Waltham

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