What to Use in a Pot to Plant a Flower

Potted flowers need good soil and water to grow.

Proper preparation of planters and containers before you plant your flowers helps ensure the plants are provided with everything they need to thrive throughout the growing season. While it may seem quicker to just add soil to the pot and plant up the flower, inspecting your pots and providing additional elements can save you resources and lead to healthier flowers later.

Drainage Concerns

Pots must provide drainage otherwise moisture builds up in the soil. Overly wet soil causes flower roots to suffocate which eventually leads to disease, rot and death. Most planters have drainage holes predrilled in the bottom. If a pot has no drainage holes and isn't made from a material that allows you to drill holes, the pot requires a liner. The liner method, called double-potting, requires planting the flower in a pot with drainage holes then placing the liner pot inside the the larger pot that doesn't provide drainage.

Container Filler

Large containers, such as whiskey barrel planters, require more soil than necessary to grow the flower. Most flowers need a soil depth between 12 and 18 inches, so anything greater than that wastes soil. Using a filler material helps conserve soil and also makes the planter lighter if you need to move it. Crushed plastic bottles and packing peanuts provide an adequate lightweight filler material that still allows excess moisture to drain from the pot. Placing a sheet of screen mesh over the filler before adding soil prevents the soil from filling in the spaces between the filler materials.

Soil Choices

Plain garden soil provides poor drainage capabilities in flower pots because it compacts easily. Most basic commercial potting soils work well for container-grown plants. Flowers that require a high-acid growing environment, like azaleas, do best with a commercial soil formulated for acid-loving plants. Both commercial and homemade soilless mixes provide a suitable potting mixture for flowers. These mixes contain peat, perlite, vermiculite, compost and other non-soil amendments that provide excellent drainage and aeration in the confines of a pot.

Nutrients

Fertilization requirements depend on the needs of the flower variety and whether the potting soil already contains fertilizer. Adding a slow-release fertilizer to the mix of non-fertilized soils before planting supplies nutrients to the flowers for about four weeks. If you don't use a slow-release fertilizer at planting, a soluble fertilizer schedule is necessary. Soluble fertilizers also replenish from slow-release applications after the four-week period. These fertilizers are applied every one to two weeks throughout the growing season.

References

• Kansas State University Extension; Alan Stevens, et al.; March 2010
• Iowa State University Extension; Growing Annuals in Containers; Cindy Haynes, et al.; June 2008