Answer: There are a number of plants which will grow well in containers. First let me say a word about containers and soil for container plants.
It is important to select containers of adequate size for the plants you wish to grow. Small, shallow rooted veggies like lettuce, raddish and spinach and many small statured annual flowers like pansey, dwarf marigold and viola will do fine in a container as small as 2 gallons. Larger plants such as tomatoes, peppers and eggplant need a minimum size of 5 gallons to perform. Larger is even better, and will allow grouping of plants. Half whiskey barrels and large terra cotta planters are great for this purpose.
Garden soil is generally not the best choice for container growing. A media (artificial "soil" mix) of ingredients such as compost, peat, sand, vermiculite, and perlite are usually used for best results. These give the characteristics needed in a growing mix: good aeration and drainage, as well as good water and nutrient holding capacity.
Types of containers vary widely and include terra cotta, stone, wood, and plastic. Even discarded items like wheelbarrows, bathtubs, old galvanized buckets, and an old boot have been used by creative (and eccentric!) gardeners. The plants do not care what they are growing in, but it is important that the container have a fairly good width to height ratio (not too tall or too shallow) and provide adequate bottom drainage.
Here are some suggested veggies for fall:
You can still get in tomatoes if you hurry. I'd suggest a fairly early maturing variety like Early Girl or First Lady. Good short statured varieties include Merced and Super Bush. Fall potatoes can also be planted now. Plant in a deep container with media filled to about a foot from the top. As potato plants grow, fill in another 10 inches with compost, old leaves or hay. The potatoes will form in this material and grow very nicely.
In September your cole crops can begin going in. This would include broccoli, cabbage, cauliflower, kohlrabi, brussels sprouts, kale, and collards. In mid September, cool season peas like sugar snaps and snow peas (need a light trellis for support) can be planted. Many of the oriental veggies like chinese cabbage, tatsoi, and daikon raddishes (need a container at least 1 1/2 feet deep) may also be planted then.
When temperatures cool off in October, begin planting lettuce and spinach.
Flowers for fall to plant now include marigolds (use transplants) and zinnia, both of which will go out with the first frost in November(?). When weather cools in October, callendula, snapdragon, stock and ornamental kale can go in. In early November set out pansies and violas.
Water as needed to prevent the containers from drying out. This may be daily or twice daily if the weather is hot or if the plant is a bit large for the container. Fertilize plants weekly with a liquid fertilizer mixed at the low label rate.
Good luck with your fall container garden!
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