Answer: Most kinds of containers (which can include pots, tubs, troughs, hanging baskets, etc.) work well for roses, though most experienced gardeners have their favorites. The important requirements are that the container must be big enough to allow for proper root development and it must provide good drainage. It should also have a wide enough base to resist being blown over in a strong wind.
The size requirement is dictated by the anticipated mature size of the plant, of course, and it is better to err on the generous side. This also ensures that the pot will hold enough soil to avoid drying out too fast. To accommodate a hybrid tea, large floribunda, grandiflora or shrub rose a 15-gallon pot is recommended. One of the smaller floribundas would be quite happy in a 10-gallon pot, while most miniatures fit well in the 4- or 5-gallon size. For temporary use, such as trying a new rose in the landscape, even the first group can be grown for a year or two in a 10-gallon pot.
Which growing media to use is another area in which personal preference reigns. Some rose growers insist on using a sterile soilless potting medium, with up to 50% Perlite added to lighten the mix and provide faster drainage. Others report success using a made-up mixture of 30% screened compost plus 30% Perlite plus 40% topsoil. To help root development superphosphate should be added to the mix (about ? cup for large pots, 1 tablespoon for smaller pots) and many rosarians also add a slow-release fertilizer.
Hope this answers all your questions. Enjoy your new roses.
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