A good container is large enough to give its plants room and hold moisture between waterings, yet manageable for the place you want to put it. Fill it with potting mix, water it thoroughly after planting and leave room for the plants to grow.
Choose a pot you can live with
One pleasure of pots is that you can move a planting when a different spot would suit it better. That is harder to do with a very large cast-stone or glazed ceramic container. Plastic, metal and terra cotta are other choices, each with a different weight and look. Think about where the pot will sit, whether you expect to move it, and how quickly its planting may dry out. A tiny pot can demand more frequent attention than you meant to give it.
Make sure the pot can drain. Then use a good-quality all-purpose potting mix rather than garden soil, which can pack down in a container. Leave some space below the rim so you can water without washing the mix over the edge. If an older planting already seems cramped, our guide to checking and repotting potted plants covers the signs to watch for.
Give the plants space from the start
A taller plant can provide the shape for a mixed container, with shorter plants around it. It is tempting to cram in everything that looks good at the garden center. Those plants will need room for their roots as the season goes on, and a crowded pot can ask for more water and attention. Try setting the nursery pots in place before planting to see how much growing room remains.
The original advice calls for working a slow-release fertilizer into the upper part of the mix. Follow the product directions for the plants you choose rather than assuming every pot needs the same amount. Once planted, water thoroughly and keep an eye on moisture throughout the season. For ideas about what can stay in a container as the seasons change, see plants for containers all year and its second part.
