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The Flower Show

Summer Solstice Refresh

June 30, 2021

leaf icon gardening

leaf icon plants

Window Box

By: Will Sulahian 

Summer is in full swing, and the summer solstice taking place is a great time to introduce new plants into your containers to refresh their look. Container gardening is a great way to showcase your favorite plants if you have limited space or do not want to commit to a full garden. Here are some suggestions you can do now:

Beat the Heat with Tropical Flair 

Some plants fare better than others in the heat of July and August such as those grown in tropical climates. One stunning tropical to consider is a variety of the Canna 'Cannova’ cultivar. Cannas are flowering plants with large, banana-like, variegated leaves that come in an array of styles. These beautiful flowers grow to heights of three to four feet, perfect for a container. While they still need plenty of water and care, they handle the summer heat and bloom up until the first frost. With a variety of flowers in dazzling yellows, reds, and oranges, these plants add a burst of color to your container and love summer sun! 

Thriller, Filler, and Spiller  

Andrew Bunting, Vice President of Public Horticulture at PHS, has some tips to make the most of your container refresh. For a container or window box that will make heads turn, Bunting recommends the Thriller, Filler, and Spiller technique. The “Thriller” of your window box should be the plant that you want to highlight or focus on. “Filler” can be anything that takes up space and fills the edge of the box. “I like to include a good amount of ornamental foliage in my window boxes. They make the box look great even if your main plants are not flowering,” says Bunting. Finally, “Spiller” plants are ones that overflow, spill, and hang out of the window box and give visual interest that extends past the container. This combination ensures the container looks good from all angles while providing a variety of colors, shapes and textures to admire. 

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Pinch and Fertilize  

These two practices will help your container and window box plants grow fuller and healthier. Pinching is the act of taking off the top two inches or so of your plant. This forces it to create more branches, resulting in a plant with more flowers and more to look at! Alongside of pinching, use a soluble fertilizer at least every two weeks to give plants nutrients and allow them to grow healthier and fuller. Be sure to use a fertilizer that is high in nitrogen and phosphorous to ensure the healthiest plant growth. 

Water and Groom  

Unless it rains, containers and window boxes need to be watered a minimum of three times a week. This is especially important during the months of July and August – be sure they are being drenched (from top of soil to bottom of container), and can be well-drained. To keep your plants looking their best, be sure to groom them and pick out any dead leaves or bent flowers. 

Keep the Garden Blooming 

No matter what plants you choose, following these tips will keep your container garden looking its best. To learn more about gardening, consider becoming a member of PHS for discounts to educational sessions, Q&A sessions with gardening experts, and more.