this is a reply to Margot who asked a question in a recent thread about soil (the OP trying a new veg garden in Surrey BC area) (See post Aug 28/20 by Margot linked here - Best way to identify and correct soil I have attached photos of the exact containers I used - I went to the nursery garden Center and photo the exact containers .... I am sure you would have same inventory on the Island I staged my large containers against a very solid concrete wall on level gravel surface with hose nearby Sun is morning to approx 2pm I used commercial container soil of various brands readily avail in SW & Interior BC but none had those moisture pellets in the mix I added some low numbers slow Release dry fertilizer I am a negligent farmer so if the plants drooped, I watered them a good soak I did put some upside down spare 1 gallon (or smaller) plastic plant pots on the bottom of the big containers cuz at time of setting this up and planting there were shortages of soil and as well store line ups and so forth (covid) and I was trying to conserve soil (budget is factor too) I stacked some of the containers as a pyramid of three total — so I place two on solid level gravel surface with approx 8 inch gap between two large pots ... then I was able to safely balance a third above that gap (I do not have kids or pets to accidentally topple this arrangement) It looked a bit ugly tho promising in the beginning and it’s been a fun experiment .... I plan to use it again next spring Yes the initial cost was a splurge $ but I can use the pots for many years ... and the soil too if I weed it and feed it accordingly Way way easier than the huge farm gardens we grew up with and not as permanent as raised beds Thé concrete wall and level gravel pad are a huge starting point bonus So far the raccoons & rats and bears and deer have left well alone. Plants include Potatoes Mint (permanent container) Some Fortex beans Zucchini (even with fresh soil it mildew’d and some flowers rotted off) Oriental Lilies Tomato Swiss chard Snow peas - they died cu we had cold and rain and rotted off. In photo - you see typical plastic terra cotta color containers — I put some in front of black ones to make it look nicer in my opinion
I am very interested to hear the thoughts about using black pots as Georgia @Georgia Strait mentioned. I did an experiment several years ago with two pots on my patio that takes full afternoon sun. One black and the other terracotta, both were plastic btw. I filled them with general purpose compost but no plants. I measured the temperature before and after 4 hours in the sun. The black potted compost was 8 ° C warmer than the terracotta potted compost after 4 hrs and the air temperature was only around 22 ° C. . Sorry but I have mislaid the paperwork for exact figures, but tbe 8° C was correct. Now if that had been my precious maple seedlings, lol, they would have been very unhappy. Yes I know I keep these in shade, but the increase in temperature is relative IMO.. I can only imagine the increase in temperature in say a 30° C + environment. So my personal conclusion was to ensure only light coloured plastic pots for areas in my garden that receives more sun. Hope nobody minds me mentioning this in a thread about growing vegetables in large containers, but I do enjoy home experiments to help my plants!!!
Acer: I have not done any soil temp experiments but it stands to reason that a black color pot would get hotter. So - the old small acreage farmers here would put black plastic (The horrible go-to of the era) to heat up soils around tomatoes etc but let’s say - not peas or rhubarb, both typical cool crops I also know that choosing planting places against large dark color solid walls (rock or concrete) helps with overnight heat I know of one Okanagan boutique vineyard that pioneered a particular red WINE grape (Nichol Wines in Naramata BC) and chose acreage with a huge natural south face rock bluff backing it for the residual heat - worked like a charm. Rattlesnakes love the same bluff too!
Yes I hope that garden centres and nurseries will take heed. But I suppose that black pots are cheaper to manufacture, so this is why we see every plant we buy is in a black pot, no matter what the growing conditions are for a particular plant.
I imagine black is the dye that covers a multitude of recycled Plastic colors from clear to green and more
