A question I often get is what size pot can I grow tomato or pepper plants in. This year I am trying different vegetables and pot size but until I get my own result here is some information: Choosing a pot that is the right size for your plants will help ensure container gardening success. A pot that is too small means your plants will not produce as much, and you will need to work harder to keep them alive. If the pot is too large, you’ll have to spend more money on potting soil than is necessary. Here’s a guide to help you choose one that is just right (source: bonnieplants.com/library/choose-right-container-plants/):
A 24-inch diameter pot will hold one of the following: large pepper, summer squash indeterminate tomato and cage, cucumber, artichoke, combinations of vegetables and herbs.
An 18-inch diameter pot will hold one of these: broccoli, cauliflower, large cabbage, small eggplant, all greens in multiples, small pepper, determinate tomato and support.
A 14-inch diameter pot works for one of these: any herbs, cabbage, collards, spinach (3 to 4), non-heading lettuce (3 to 4), arugula (3).
A 10-inch diameter pot will hold one of these: small herbs, strawberry, lettuce.
“Keep in mind that not all pots are round and tall. Shallow-rooted plants such as lettuce will be happy in a container that is wider than it is tall. However, most vegetables will need deeper pots. Broad plants such as a zucchini or pumpkin will benefit from a container that is both broad and deep. Half-barrels are perfect for bigger plants such as tomatoes and squash. Use your best judgement to give your plants plenty of room for optimum harvests. Sometimes experience provides the best advice for the future.”
I have many different size pots so I found some of the measurements long ago on the internet. It seems that each company has a different size for their pots so here are some measurements, in inches: 10-gallon 14 1/2 x 14 1/2; 10-gallon, squat 17 1/4 x 12; 15-gallon 17 1/4 x 15 1/4; 15-gallon, squat 19 1/2 x 12; 20-gallon 19 1/2 x 17; 20-gallon, squat 22 1/4 x 13 1/8; 25-gallon 22 1/4 x 18.
From another site: 4” pot = pint (0.5 quart); 5-6” pot = quart (0.25 gallon); 7-8” pot = 1 gallon; 8.5” pot = 2 gallon; 10” pot = 3 gallon; 12” pot = 5 gallon; 14” x 12” pot = 7 gallon; 16” x 12” pot = 10 gallon; 18” pot = 15 gallon; 24” pot = 25 gallon; 30” pot = 30 gallon.
Pot size in centimetres–inches–millimeters : 5cm = 2inch or 50mm; 10cm = 4 inch or 100mm; 14cm = 6inch or 140mm; 17cm = 7 inch or 170mm; 20cm = 8 inch or 200mm; 25cm = 10 inch or 250mm; 30cm =12 inch or 300mm; 25 or 30 litre = 12 inch or 300mm; 45 litre = 16 inch or 450mm.
Hope I didn’t confuse you as much as I am. A five-gallon paint bucket makes a good size container as long as you have drainage holes in the bottom.
– Jocelyne Sewell is an organic gardening enthusiast in the North Okanagan and member of Okanagan Gardens & Roses Club. Her column appears every other Wednesday.