The color by itself likely won't kill the plants. After all, nurseries are not in the business of killing plants. The black will heat up more but likely not enough to kill plants by itself. I'd make sure the containers are of adequate size for the plants, though. Tomatoes need at the very least 5 gallon, but 10, 15 or 20 gallon would be better.

More space for roots and water and the bigger mass inside the pot don't heat up or cool off as quickly.

If you are concerned about the color, painting the pot or wrapping it in something lighter colored are always options.

There is nothing wrong with using black nursery pots in cold weather zones. I'd be more careful in I lived in AZ or CA, but zones 2 to 5 should not present any problems. In some cases, it may help the soil retain some heat as temperatures dip in the evening.

As for pot size, consider whether you plan to extend a plants growth over multiple seasons. Some people prefer larger pots (greater than 10 gallon), but they typically live in warmer zones with longer growing seasons. Since they have the time to grow larger plants, larger pots can be helpful. I live in MN and since you live in NY, this would not be an absolute requirement. I'd go for a 5 to 10 gallon pot. There is no sense on spending a fortune filling 20 gallon pots with mix for one growing season.

I am using them in California without trouble. I've played with my point and shoot thermometer. The black pots are cooler than ambient air when they have water, energy goes into evaporation, evaporation cools the soil.

Commercial growers all around me use them, of course. They pack them in into blocks. It is the natural impulse for home growers to space them out, but if they do looks warm, a cluster could help.

Yes black nursery pots are safe to use. I have been growing plants in them for years, although I am new to the 5-1-1 mix. If black nursery containers were not "safe" then garden centers would not use them.

However, there might be specific plants that would do better in cooler soil temps and they might benefit from growing in a white or light-colored container. It also depends on where you live. Summer temperatures in Arizona or Florida might have more impact on soil temps than in the Northeast or Upper Midwest.

If you can keep the soil relatively cool and provide enough water to your plants without soaking the roots and causing root rot, then you should be fine using black nursery containers.

One option I have heard of is drilling extra holes in the side of containers for better drainage. I'm not sure if this would do anything to reduce the heat of soil and roots in a black container or not.

TYG

Yep I thought they would be safe. A fellow container gardener gives me "crap" about using them. I'm pretty good about watering so.. Thinking about putting saucers under the containers also

Best thing about the black nursery pots is that you can get them for free at places like Lowes that do pot recycling. (Or by cruising up-scale neighborhoods in the spring.)

Dennis

"but zones 2 to 5 should not present any problems"

They don't present any problems here in 7B

I don't use saucers on mine, I guess I'm lucky that I can have them on a brick-over-sand patio. I actually like the massive drainage of the commercial pots.

If your friend asks again, ask him back how he can survive with one tiny drain hole, rather than professional drainage.

if you think you have a problem with the heat in hot areas. .consider planting the pots in a few inches of garden soil.. this should help in lowering the soil temp when the roots grow.. hotter climate.. lower.. or plant marigolds around... or another summer annual that will grow around the pot and absorb some of the excess heat!