The charm of vibrant bushy flowers, herbs, and vegetables offers a colorful greeting that is well worth the trouble, especially when your plants are thriving.
Caring for a few potted plants on the porch or patio can add a whole new agrarian dimension to your life. If the idea has intimated you because of a bad experience with a plant in the past, don’t let it stop you from trying again! As career farmers, my husband and I have had plenty of expensive mistakes that we chalk up to learning. As Will Rogers said, “A Farmer has to be an optimist, or he wouldn’t still be a farmer.” I challenge you to be an optimist and follow these 6 tips for successful container gardening. Your success will open doors, and your thumb will turn green!
Tip 1 – Unobstructed Water Drainage
What Roots Need
The roots on plants need air space within the soil. Without adequate water drainage, roots that stand in water will suffocate and die. Choose a pot that has drain holes or drill them yourself. No gravel or coarse material is necessary at the bottom of the container. Adding “drainage material” to containers will only hinder water movement, according to Dr. Linda-Chalker Scott WSU, so skip the search for pieces of broken pots or rocks.
Several years ago, I filled a large pot with commercial potting mix. The large size of the pot meant that I used almost an entire bag of potting mix. The following spring, I thought I could refresh just the top 8-10 inches of potting soil with a new potting mix rather than replace all soil in the entire pot. When I decided to clean out all of the pot the following year, I encountered this thick mat of root buildup. You can see in the photo above the roots blocking the drainage holes. I learned my lesson! I now empty my pots each spring before planting to ensure nothing is blocking the drainage holes; then, I always add a new commercial potting mix.
But What If The Pot Has No Drainage Holes?
Fear not! You can still use a neoclassical European pedestal planter with no drainage holes for that “I live at a winery” look. The trick to using pots with no drainage holes is to double pot.
Add three or four fist-sized rocks. The rocks elevate a pot liner to allow water drainage to the bottom of the planter.
This pot liner fits perfectly and has drainage holes! You can find these at Home Depot in the general vicinity as the pedestal planters.
Creating Drainage Space
Now the plant that goes in the pot liner will have drainage. Measure how much water is needed to water your plant so that water doesn’t overfill above the rocks that hold up the pot liner. The important point is to keep the pot liner from sitting in water. Roots need aeration and will drown when sitting in water. Before I started my master gardener training, I had a lemon cypress tree that died in a pedestal planter like this. At the time, I didn’t know why. Now I know! I had overwatered the plant so much that the pot liner stood in water. The plant’s roots drowned, then rotted, eventually killing the plant. Now I know to pull out the pot liner and empty the extra water in the pedestal planter if I overwater. Since my lemon cypress tree is no more, what would look good in this type of planter?
Mint in Pedastal Planter
Herbs do well in containers close to the house. When I’m making a mojito drink, fresh mint leaves growing nearby are always delicious! Containing the mint in this pedestal planter makes sense for three reasons: 1. Mint is invasive and will fill its space and more. 2. With regular pruning and grooming, mint is beautiful! 3. Mint is always close by for that end-of-the-day medicinal.
Tip 2 – Good Potting Mix
Potting Mix Defined
The soil within a pot experiences more heat because of the sun, wind, and air temperature surrounding the pot. Soil compaction and loss of nutrients can occur because of the limited space and frequent waterings. The research-based ingredients in a quality commercial potting mix combat the heat, compaction, and nutrient loss problems of container living. I use Miracle-Gro potting mix because of the ingredients that promote good drainage, aeration, initial balanced nutrition, and moisture retention. Our temperatures in the summer can get as hot as 107°, and I water daily. The moisture retention properties of organic matter like peat moss, sphagnum moss, or coir help plants survive these hot temperatures.
How Much Potting Mix
Fill the pot with a potting mix to one inch from the top to allow for watering. When placing the new plants into the pot, add water to tuck in the plants and fill in the potting mix all around the roots. I need to feel where the new plant is, so sometimes I pull off my gloves to tuck the transplant into the potting mix.
Tip 3 – Right Plant Right Place
Matching Plants & Place
In considering the placement of the pot, also consider the appropriate flowers or plants for that location. A pot in full sun will need flowers that flourish in full sun and vice versa for a pot in the shade. The basket of flowers on my daughter’s sunny southern porch includes sun-loving Calibrachoa, lantana, and creeping jenny. Doesn’t that creeping jenny give the basket a dramatic appeal by spilling over the edge?
How to Arrange the Flowers
Whether you’re considering sun-loving or shade-loving flowers, there is a recipe for arranging different flower types in the pot. The recipe calls for the “thriller, filler, and spiller” flowers. A thriller plant is the tallest and provides a dramatic color or shape to the middle of the pot. The shorter filler plants surround the thriller adding texture, mass, and color to complement the thriller and not overshadow it. The spiller plants spill over the edge of the entire pot to soften the overall effect. This year in my full sun pot, my thriller is purple fountain grass, Rubrum, the filler is million bells, Calibrachoa, and my spiller is Silver Falls, Dichondra argentea.
When you shop for your flowers, this resource sheet listing flowers by full sun or shade in the categories of thriller, filler, and spiller to make a spectacular flower pot. I try to organize my shopping list in advance of the shopping at the greenhouse. Once I get around all the purchasing options, I lose focus!
Tip 4 – Water & Fertilize Regularly
Daily watering is essential to a pot outside in the sun and wind. Containers need water more frequently than plants in the ground. An automated drip system is ideal but still requires occasional checks for reliability. Stick a finger into the soil up to your first knuckle to check for moist soil. If it’s dry it’s time to water! The daily temperatures will dictate the watering schedule. When the temperatures get above 75° daily watering is important to maintain plant health.
Commercial potting mixes offer “initial balanced nutrition.” After 2 -3 weeks, plants use up the nutrients included in the potting mix. They may lose their bright green color, bloom less frequently and look weak. Regular feeding with liquid, dry or timed-release fertilizer will support the ongoing needs of the growing roots. Look for balanced and complete fertilizers such as 5-10-10 or 10-10-10. The numbers stand for (N) Nitrogen, (P) Phosphorous, and (K) Potassium. The higher the number, the more concentrated the nutrient is in the fertilizer. These macronutrients are key to maintaining the overall health and beauty of the plants in your containers.
Tip 5 – Prune and Groom
In the same way, people need regular haircuts; plants require some pruning and grooming throughout the season. Every 6 weeks, I get a haircut to maintain shape and style. I do the same for my container plants, so they look strong and healthy.
Cut off the spent flowers and if the plants become leggy or have died, do some pruning to shorten or remove dead or weak stems. The stem cuts encourage new growth so that plants are bushier, form new flowers, and are more compact.
Pruned flowers and herbs grow better, taste better (herbs), and are bushier.
Prune To Fit Your Space
Shyla doesn’t have space in her backyard for a garden, so she grows what she needs in containers. Her containers of tomatoes and herbs brighten her back porch and provide an entertainment factor. If her plants get too big, she can prune them to fit her space. Lady, her dog, has been known to assist in harvesting by snacking on tomatoes that grow where she can reach.
Tip 6 – Monitor Pests and Diseases
Know Your Plants
Organic farming requires rigorous IPM, integrated pest management. If you want to minimize pests and diseases in your pot, it begins with frequent monitoring and knowing your plants. Watch your pot for everything that’s happening with your plants. This is the entertainment factor! By knowing your plants, you’ll know immediately if something is wrong. If you discover a pest, you’ll need to identify it accurately to know how to manage it. If you have trouble identifying it, take a close-up picture. Share the picture with your local Master Gardener Program for assistance with identification and management strategies.
In this picture, the little insects on the underside of the leaf are aphids. Ladybugs dine on aphids, so a great organic management method encourages predator insects such as ladybugs, lacewings, hoverflies in the yard, and pots. I recommend a magnifying glass to get a good look. A $10 jewelers magnifying glass does the job and is something organic farmers have on hand always in their IPM toolbox. Even with a full toolbox and close inspection, it may be hard to name the problem. Be sure to ask for help.
Ask Master Gardeners Questions
Plant disease such as powdery mildew is another plant problem to watch for. Fungi are responsible for the white leaves on these petunias. If you allow this pathogen to infect all of the leaves on the plants in your pot, it will compromise the plant’s health by destroying its tissue. Remember, if you’re unable to identify the disease, take a close-up picture and email it to your local Master Gardener Program.
The secret 7th tip is to enjoy your container gardening experience. Plants are known for boosting mood, increasing creativity, reducing stress, and making social connections. The daily inspection of your pots can provide endless micro-pleasures in snipping, squishing, and pinching while creating the perfect growing environment. Then as you share information with others or reach out for help, doors will open, and your inner agrarian will emerge. That’s when you’ll notice your containers are lovely and your thumb is green!