Raising flowers in planters is ideal for gardeners who have limited growing space, according to Cornell University, as well as those who want to place flowers where there's no soil, such as on a patio or deck. Various factors can affect the success of growing flowers in a planter, including the planter itself and how you care for it after filling it with perennials or annuals.
Types of Planters
Planters come in a wide range of sizes, from small, quart-sized pots to massive 50-gallon pots. Construction materials for planters likewise vary and include clay, plastic and wood. Whatever you choose, West Virginia University recommends only using pots that have drainage holes on the bottom. Size-wise, the university suggests any planter that's a minimum of 8 inches deep and 6 inches in diameter for most annual flowers. If in doubt, it's always best to use a larger planter.
Container flower gardening requires a good potting mix to prevent problems like root rot, according to the University of Minnesota. The university recommends using a commercially prepared potting mix, available from most garden stores and nurseries, or making your own mix by combining equal parts of soil, compost and vermiculite or sand.
Set the flower planter on bricks to allow for proper drainage out of the pot's bottom holes, according to Cornell University.
The flowers you choose to grow in your planters must be chosen for the area in which the planter will be placed, according to Iowa State University. For example, pots that will be put on an open, sunny deck should only be planted with annuals or perennials that thrive in full sun. If you're populating the planter with different types of plants, the university suggests selecting plants that have similar growing needs.
Due to the contained nature of a flower planter, plants grown in such containers need regular feeding to sustain proper and vigorous growth. For the best results, fertilize bi-weekly with any water-soluble fertilizer intended for potted plants, according to West Virginia University. Because potted plants are more susceptible to overfertilization than plants grown in the ground, all fertilizers should be applied according to their labeled guidelines.
Watering requirements vary according to the climate, the planter's position (e.g. sunny or shaded) and the planter's construction material. Porous flower planters like clay or wood pots loose moisture faster than plastic pots, and smaller pots heat up quicker and evaporate water faster than larger pots. To best gauge watering needs, the University of Minnesota recommends watching the planted vegetation for signs of drought stress, such as wilting or curling of the leaves.