How to Plant in a Planter Box

Planter Box Type and Positioning

• 1

  Determine the type of planter box you'd like. Formal white painted boxes or unpainted redwood boxes each create different statements in the garden or on a deck. Create a feeling of outdoor rooms using custom planter boxes styled after your house's architecture.

• 2

  Positioning your planter box is important for plant choices. Find the position your planter box will occupy and check the type of sun at that location throughout the day. Assess the amount of wind and cold a planter box will receive.

• 3

  Place planter boxes near a convenient hose or automate watering by locating planter boxes near existing drip irrigation systems. Run an additional line up through the box bottom to the top of the planter box and install a bubbler later at soil level.

Planting Design

• 4

  Draw your basic planting plan on a sheet of paper with plants you would like to use represented at mature size. Use it as a guide to ensure all your choices will fit your planter box when full grown. Use a good gardening book if you're not sure of any plant's eventual size. Remember that your planter box will be seen from all sides unless placed against a wall so place tall plants in the middle.

• 5

  According to P. Allen Smith in his 2005 book, "Container Gardens", use the three basic plant forms to create a dynamic design. Mix tall, round and trailing plants for lasting eye appeal. Put plants next to each other when choosing at nurseries or garden centers to see how your choices combine.

• 6

  Think about bloom times and flower colors for your design. Flowering season is short for some annuals; consider a mix of annuals and perennials. Stretch the bloom season of your planter box by including bulbs.

Choose Your Plants

• 7

  Consider foliage when choosing plants. Garden plants grown primarily for their foliage make attractive accents. Black sweet potato vine, coleus, elephant ears, black mondo grass, variegated ivy, ferns and dusty miller fall into this category. Other plants have spectacular flowers and interesting foliage. Canna lilies, with their orchid-like flowers, fall into this category.

• 8

  Choose small evergreens for permanent foliage and winter interest. There are many varieties that can be mixed among flowers. Dianthus, evergreen candytuft, evergreen dwarf hollies, hebe, ivies, curry plant, dwarf junipers, heather, sedums and hen-and-chicks are dependable evergreens with varied forms.

• 9

  Choose plants with similar soil and water requirements for easiest care. Look at plant labels in nurseries and garden centers to check your choices. Buy a potting soil developed with nutrients for the types of plants chosen.

• 10

  Pick only healthy plants from local garden centers and nurseries. Mail order plants require more time to grow and reach bloom stage. Shun plants with withered leaves, wilting, yellowing, straggly growth, or obvious signs of pest infestation. To lengthen your planter box bloom season choose healthy flowering plants in bud, not in full bloom, when first planting.

Fill the Planter Box

• 11

  Prepare your potting mix for planting by dampening thoroughly.

• 12

  Cover the base of the planter box with clean pebbles or broken pottery chips to promote drainage.

• 13

  Fill the planter box halfway with potting mix. Place your plants in the planter box while still potted to experiment with final placement.

• 14

  Remove plants from their pots, loosening the roots at the base of each root ball. Place in final positions in the planter box firming more potting soil around them.

• 15

  Check the final soil level; it should be at least ¾ inch below the planter box rim to keep water from running off. Water planter box well initially with gentle spray till water runs out the bottom and keep to a watering schedule. Feed regularly with fish emulsion or liquid compost.