I have 4 of the old original black ones, 2 green ones, and a couple of the brown earth tone ones. No difference in plant performance. What makes the MOST difference is the mix you use to fill and the types and number of plants you grow in them.

Only 1 indeterminate variety or 2 determinate varieties per box and after trying several different mixes over the years I went back to Miracle Grow Potting Mix last year with excellent results. Never use the MG Garden Soil or the MG mix with the moisture additive IMO. Keep the water resivoir filled at all times and feed regularly.

Dave

Oh, thank you so much for this helpful and quick reply. I have a new bale of ProMix here that I thought I could use but it's super to know the MG potting mix also works so well in these boxes. ProMix isn't always locally available and is so expensive to have shipped. MG potting mix is almost always available locally.

How often do you need to feed? I've never used this type of container and somehow thought it was place the strip of ferts in indentation on surface of growing medium, place the cover and then keep irrigated.

My thanks again for your helpful advice, Mary

1. I think dark colors (especially black) absorb more heat and reflect less.

"How often do you need to feed? I've never used this type of container and somehow thought it was place the strip of ferts in indentation on surface of growing medium, place the cover and then keep irrigated."

That is what the manufacturers state but it is often discussed on the forums there that it isn't enough for the whole season anyway and that its effectiveness all depends on your climate and how much rain you get for top watering. We do put in the fert strip, just don't count on it for that is needed. Several different methods for later feedings have been suggested but what works best for me in my dry climate is to mix up some some 1/2 strength MG fert and pour it down into the water well every 7-10 days.

ProMix is great - when you can get it.

Dave

Thank you! I use MG reg garden or super bloom grains diluted to feed my seedlings as they grow out and to hand water my flower pots during the summer so I have that on hand. Will be super easy to add a weak drink for the tomato plants along. Thanks for the explanation and the growing tip.

Mary