Flower pot size?

Hi All,

My question is, how do you determine the size of a flower pot for a particular plant or flower or combination? A pot filled with 12 inch tall marigolds and a pot filled with 4 foot tall sunflowers would obviously both require markedly different sized pots. So, how do you make a good choice when there are so many different sized pots to choose from? Thanks

You have to think of how big the plant(s) will ultimately get first. Then choose accordingly.

It's difficult to work out the size of pot from your ways, the problem is, the 12 inch Marigolds say 6 of them will be more than happy in a 12 inch pot, as they are annuals and grow one season very fast, these plants want to set seeds as soon as pos therefore you dead head them to prevent them from flowering once and then dying off as they have done there job of germination, flowering and making seeds, job done.

The tall sun flower which has a larger root (as you would expect) but one stem, will also be happy in 12 inch pot as there is enough soil, you put a cane into pot for support and the sunflower will grow tall up it's support and be just as happy.

My own way to find a pot to suit is if I buy a plant (perennial, Shrub or tree) then I re-pot into 2 sizes larger than I bought the plant in, this way the roots are able to spread enough, there is not too much room to prevent the plants from flowering as they want to fill a big pot with roots before using up energy for nice big flowers or larger bunches of flowers whichever is the case.

If I am growing from seed like Marigolds / Sunflowers etc, then the seed packets normally help with this info, I know this sounds silly but it's more practice than teaching that will help, remove your plants from the pot, stick the plant into a slightly larger empty pot, if there is enough room for soil under, around and a tiny bit on top, then your fine, perennials can be re-poted every second year and shrubs, small trees would normally last in a rot 2-3 years before I would re-pot, any faster re-potting required and I would stick them in the garden or re-pot EVERY year, this is expensive and such extra work. Hope this gives you some ideas and thoughts.
Good luck. WeeNel.

Hey it also depends on the spread of plants, I mean whether they grow like shrubs or how you want them to prune.But one thing I can say is if the plants have tap roots then good depth is needed, if they are ground covers like Mentha species (Example : M.spictata) then those generally have shallow roots and I feel rectangular containers with more surface area(since these plants propagate by runners and multiply) and a depth of about 6 inch will do.

Also note that it depends on the population, I mean if u want to grow more plants in one container then you should select the container in such a way that they grow freely instead of competing (with roots) and neither of them growing as expected.

My advice would be to grow easy to grow vines like clitoria ternatea in hanging containers and Perennials like Chrysanthemum in 6 inch pots, shrubs like Hibiscus in 12 inccers.

But be wary of plants having tubers like potatoes , they neew more soil.

On a monthly basis check that the roots don't poke out from the bottom drainage holes, if you see such things then select next higher pot (but not big by more than 2", ex:If 6" then next 8").

Well this is all I know and gardening comes through experience, and certainly DG is helping us all to put forth our views.

The below info is from a guide to container veggies.

The size of the container you chose will depend on the mature size of the plant it will contain. A plant will stop growing and become stunted if it is growing in too small a container. Examples of plants and recommended container volumes are:


Peppers, chard and dwarf tomatoes soil volume of 1-2 gallons per plant

Full-sized tomato plants, cucumbers soil volume of 4-5 gallons per plant

Lettuce, radish, onions, and beets 6"-10" diameter pots



My great Aunt always said the "rule of thumb" was to use a pot that left about 2 inches between the root ball and the side of the pot with about 4-5 inches of soil beneath the plant and at least 1 inch of pot above the soil line to allow for watering. This method has generally worked for me with most Non-vegetable annuals and perennials.



This message was edited Feb 5, 2012 1:23 PM