General Container Gardening

Choosing a pot and growing mix: In addition to our Annual Collections, most of the plants we offer can be grown, either singly or in combination, in containers. Any container with a drainage hole in the bottom will suit. The growing medium in containers must drain much more quickly than garden soil.

Planting: Begin by adding potting mix to the container until the container is about ¼ full. (If you use a dry, peat-moss-based mix, you must first moisten it by placing it in a plastic tub or a wheelbarrow and slowly adding water until the mix is moist but not soggy.) Next, set the plants on the mix one by one, spacing them much more closely than you would when planting them in the ground. Put the tallest plants in the center of the container. Surround them with the shorter, mounding plants, and put trailing plants along the edge. When you are pleased with your arrangement, add potting mix to bring the level to within an inch or so of the container's rim and firm lightly. Finally, water thoroughly.

Container care: Plants in containers need special care. They dry out more quickly than plants in the ground; in the heat of summer, you may have to water them daily. Because of the need for frequent watering, nutrients soon wash out the bottom of the pot. To keep annuals growing and flowering, we suggest you water with a balanced, water-soluble fertilizer mixed as directed, every other week in summer. (Other plants—bulbs, perennials, and shrubs—need less fertilizer; a half-strength solution applied once a month through August is enough.) Our Container Booster (51002) is a mix of 10 ingredients, organic and mineral, that will revitalize last year's potting soil and slowly release nutrients throughout the season. All-Bloom Fertilizer (51014) is a 15-30-15 product that can be diluted in water and applied regularly during the growing season. Finally, to look their best, all plants in containers need regular grooming. Remove spent flowers regularly and prune vigorous growers to keep them in check.

Preparing for winter: In climates where winter temperatures drop well below freezing, containers should generally be dismantled in fall. Bring tender plants indoors or toss them on the compost heap; plant hardy bulbs, perennials, and shrubs in the ground. Most containers should be emptied of potting mix and stored under cover; only plastic and fiberglass pots can be left out over winter without cracking. In mild-winter climates—say, Zone 8 (10°F) and warmer—hardy plants can generally be left outdoors in containers with little risk either to the plants or to the pots.