I live in the toronto Beach area. My backyard is on the west side of the house. Last year I created a garden bed that is 30 inches by 84 inches. The bed is enclosed by a driveway and stone patio. The garden bed is about 12 inches deep. I want to plant 3 rose of sharon plants in that garden bed. The dirt soil was poured in last year from bags I purchased at the loblaws garden center. Will my plants survive the winter or do the garden bed need to be deeper or even wider .
Rose of Sharon (Hibiscus syriacus) is one of the few shrubs to offer an abundance of blooms later in the summer and this is one of the reasons for its popularity. Its rooting system is reasonably shallow and close to the surface of the soil, so the depth of your bed should be adequate. Mulching with a 2 to 3-inch layer of organic material around the root zone in the fall can help to protect your Rose of Sharon over the winter. The spread of a Rose of Sharon can range from 4 to 10 feet, and this can be managed by pruning as needed. Check the label of the variety you are purchasing for its size at maturity. You may find that two specimens will fill your space.
Although the Rose of Sharon can tolerate poor soils and drought in sun or partial shade, it is always a good idea to amend your soil each year with organic material, particularly in a small, shallow bed. Adequate watering is necessary for your Rose of Sharon to look its best. Your plants will also benefit from an application of a balanced 10-10-10 fertilizer after dormancy and when leaves are emerging in spring. A mid-summer application of a low nitrogen 0-10-10 fertilizer will promote root health and flower production. Always follow the fertilizer package directions carefully and water the plant well before the fertilizer application in order to protect roots from chemical burning. It is worth noting that Rose of Sharon can be susceptible to winter kill during very cold winters but all in all, it is a lovely plant whose beautiful blooms are well worth having in your garden.