Rose of Sharon Trees (hibiscus syriacus) boast all-around beauty and versatility. In tree form, they're an easy, non-stop bloomer, bringing a splash of summer color to your garden. Growing 8'–10' tall with heads that can span 5'–6' across, they're ideal as a single garden centerpiece or for lining a walk, drive, or entranceway. When not in bloom, the foliage is dark green and heavily textured.
Quick Reference Planting Guide
- Location: Full to partial sun.
- Hardiness: Zones 4–9.
- Planting Distance: 10' apart.
- Mature Height: 10' with a head span of 5'–6', which will take up to four years.
- Bloom Time: Mid-summer to frost starting the second year.
- To Plant:
- Dig a hole large enough to give the roots plenty of room, with a few inches of space beyond the root tips and the sides of the hole. Build a mound of soil in the bottom of the hole and spread the roots in a natural position atop the mound.
- Position the plant so that the previous soil line is even with ground level. The stem/trunk will be darker in color below the original planting line and lighter in color above it.
- Once the plant is positioned at the proper planting depth, begin filling the hole with soil. Work the soil around the roots with your hands. When the hole is half filled, tap the soil to remove any air pockets.
- Fill the planting hole with water and let it soak in. Straighten the plant in the hole and finish filling with soil.
- Form a “saucer” of soil around the edges of the planting hole and fill it with water.
- To help anchor the roots, be sure to stake the tree. This will also maintain upper balance so that the trunk will continue to grow straight.
These trees do well in most garden soils but, for optimum results, improve your soil as follows:
- Spade or rototill the soil to a depth of 2'–3'.
- Mix in a 2"–4" layer of dehydrated manure, garden compost, shredded leaves, and/or peat moss. After active growth begins, periodically feed with a water soluble flower booster. Plants in containers need more frequent water and feeding, especially when in active growth, bloom, or while setting fruit.
- Watering: Never let your new transplants dry out. Your tree requires 1" of rainfall, or equivalent watering, each week.
- Mulching: Apply a 2"–4" layer of shredded bark, compost, or other organic mulch around your plants to promote moisture retention, maintain even soil temperatures, and discourage weed growth.
- Weeding: Keep the area around your plants free of weeds. Weeds compete with plants for food, water, and light. Walk around the garden periodically and pull weeds, including the roots, as soon as you see them. Mulch also assists in keeping weeds down.
- Deadheading: Remove spent blossoms to promote additional blooming. Pinch or cut off when they fade, but leave as much foliage as possible.
- Grooming: Clip off unsightly or dead growth to maintain the plant's shape. Cut flower stalks between the bottom blossom and the uppermost leaves.
- Feeding: Discontinue any feeding after September 1. Your plants want to harden off for winter dormancy.
- Winterizing: After the ground has frozen, apply a winter mulch of evergreen boughs, straws, or leaves to prevent lifting of the plant’s roots during freezing and thawing periods. As soon as the weather warms, remove any mulch from in-ground plantings. At the same time, prune off any dead wood. This is also the time to bring any containerized plant back out into the garden sunlight.