Container Planting: How And When To Start

One of the great things about gardening in containers is that you can put them anywhere. You don’t need to till the ground or have a large yard—just a small, sunny space – such as a porch or patio – to create your own outdoor oasis. Container planting is also a very nice way to maintain multiple gardens in small spaces.

Wait until the danger of frost is past to plant your outdoor containers. Frost dates vary year-to-year. To estimate the average final frost date for your area, consult the Farmer’s Almanac or the National Gardening Association. For most plants, the process for prepping and nurturing is the same.

HOW-TO CREATE A CONTAINER GARDEN:

PICK THE POT: Almost any type will do, as long as it has drainage holes, preferably on bottom and sides. To protect the surfaces they sit on, raise pots on terracotta pot feet, bricks, or wood pieces.
SELECT THE SPOT: Determine how much sun your plants will need. You can find this information online, or on the tags in plants purchased from your garden center. For plants that require full sun, place pots in a spot that receives six to eight hours of direct sunlight a day.
PREP THE SOIL: Potted plants need potting mix, a nutrient-rich type of soil specially designed for containers. I prefer to use an organic mix such as Miracle-Gro Organic™ Outdoor Potting Mix. First cover drainage holes with fabric or broken ceramic shards (to keep soil from falling out), then moisten the mix before adding a layer to the bottom of the pot.
POT THE PLANT: If planting purchased seedlings, check the tag to find out how much space is needed between individual plants. Gently loosen any bound roots of the plant (you can use your fingers) and place them in your pot to determine how much more dirt you’ll need to cover the roots. The leaves should appear just above the surface of the soil. Add enough soil to cover the roots and fill the pot to an inch below the container’s rim. Pat down the soil firmly, then add water until it starts to drain through the holes.
FERTILIZE FREQUENTLY: Unlike in-ground plants, those in pots have fewer nutrients to draw on because of the limited amount of soil. Add a slow-release fertilizer a few weeks after planting, or a diluted liquid organic fertilizer every two weeks during the growing season. Two excellent options are Miracle-Gro Organic All-Purpose Plant Food (granular) and Miracle-Gro Organic™ Plant Food (liquid).
WATER WELL: You’ll know the plant is thirsty when the soil feels dry an inch below the surface. Add water until it starts to drain through the holes, but don’t overdo it (or you’ll also drain out nutrients). Never let the soil fully dry out.
PRUNE AS NEEDED: Some flowering plants require deadheading to encourage new growth. Pinch or snip off dead blooms during the season. Plants that are covered in small flowers, or that begin to wilt in late summer, should be cut back no more than one-third when the blooms are spent; don’t worry, the plant will grow back in no time.

MARTHA’S TIP

If you have larger planters, like I do, it’s a good idea to line them with used bubble wrap (or garbage bags) before planting. This is a great way to reuse and repurpose wrapping that may have accumulated over the winter months from package deliveries. Filling the bottom of large pots benefits plantings in several ways – it’s more economical, easier to move and better for drainage and root growth.Here is my process for filling large containers.

Fill the container partway with reused plastic bags or bubble wrap. Poke or cut holes in the plastic bags or bubble wrap for better drainage.

Position a pot the right size for your plant inside the larger container, leaving room for soil inside both pots.

Then I add nutrient-rich potting soil to the pot. A good option is Miracle-Gro Organic™ Outdoor Potting Mix.

The pot is then covered with more soil mix, and I will add a ground cover that will spread and fall over the sides of the container in the next several weeks. This year I am using helichrysum, dichondra, and lysimachia.