How to Grow and Care for Hibiscus

In this article, we'll cover:

• Comparing Tropical Hibiscus, Perennial Hibiscus, and Rose of Sharon
• Choosing When and Where to Plant Hibiscus
• Planting Hibiscus
• Caring for Hibiscus
• Propagating Hibiscus
• Overwintering Tropical Hibiscus

Growing hibiscus is an easy way to add exotic allure to your garden. With their big, vibrant flowers, these plants put on a big show during summer. The first step to growing and caring for hibiscus is understanding the three main hibiscus types: tropical, perennial, and common (a.k.a. Rose of Sharon). Once you understand the needs of your preferred hibiscus, you'll find that these flowering plants are a wonderful addition to your garden or landscape.

Comparing The Types of Hibiscus

There are three main types of hibiscus: tropical hibiscus (Hibiscus rosa-sinensis), perennial or hardy hibiscus (Hibiscus moscheutos) and Rose of Sharon (Hibiscus syriacus). All three types love the sunshine and have colorful flowers. While these hibiscus types are all stunning, they have very different environmental preferences.

Tropical hibiscus plants are what you think of when you picture lazing by the pool in Florida or see blooming all over the islands of Hawaii. The blooming shrubs can also have yellow, orange, lavender, red, white, or even bi-color flowers. They have a longer blooming season than perennial hibiscus. While tropical hibiscus can only survive winter outdoors in zones 10-12 (find information about hardiness zones here), they make great container plants for poolscapes and patios during summer in cooler areas. You can sometimes find tropical hibiscus plants as "standards," which are plants that have been trained to look like trees.

Perennial hibiscus, also called hardy hibiscus, form a large bush, but die back to the ground each winter. These hardy hibiscus plants can survive the winter in zones 4 to 9. They typically have larger flowers and lighter green leaves than tropical hibiscus, but the bloom size and leaf color vary greatly from species to species. Some plants can grow to be quite large (up to 7 to 8 feet tall). Perennial hibiscus blooms in mid to late summer. Flowers are typically white, pink, lavender, red, or burgundy. If you have a smaller garden, look for a dwarf variety.

Rose of Sharon is a woody shrub that grows 8-12 feet tall and loses its leaves each fall. Hardy in zones 5-9, they love hot weather and are great for attracting pollinators. The flowers of Rose of Sharon are 1-3 inches in diameter and come in vibrant shades of yellow, pink, purple, lavender, and white. The flowers also bloom a bit earlier, from spring to summer. While the flowers are smaller, the plants themselves grow quite large, and you may see Rose of Sharon plants used to create a beautiful flowering hedge.

Choosing When and Where to Plant Hibiscus

Tropical Hibiscus: Tropical hibiscus needs moist but well-drained soil. This warm-weather plant does best when planted in containers in spring. Unless you're in the southern most parts of Florida (zone 10 or higher), you'll need to keep it inside until nighttime temperatures are consistently above 50 degrees.

Perennial Hibiscus: Perennial hibiscus grows best in moist soil that never completely dries out (this type can handle a bit more water than tropical hibiscus). If you have a low spot in the garden, perennial hibiscus is an excellent bet for mid- to late-season color. Plant perennial hibiscus plants in the spring so that they have an entire growing season to establish a good root system. When planted in the fall, a perennial hibiscus might not return as reliably the next spring as one planted earlier in the year.

Rose of Sharon: Rose of Sharon prefers moist, well-drained soil. Preferring full sun to partial sun, these hibiscus are less fussy about location and soil conditions. Be sure to give these plants plenty of space to reach their mature size as they can grow quite large – 8-12 feet tall and 6-10 feet wide! Read your plant tag to confirm how much space your plant will need. Rose of Sharon may be planted in spring or fall.

Planting Hibiscus

To plant perennial hibiscus and Rose of Sharon:

1. Dig a hole that is twice as wide and just as deep as the plant's root system.
2. Remove the plant from its plastic pot and settle it into the planting hole.
3. Fill in around the root ball with a 50:50 mixture of the soil you removed and Miracle-Gro® Garden Soil for Flowers to grow bigger plants with more blooms (vs. unfed plants).
4. Water well after planting.

To plant tropical hibiscus:

1. Select a container that is no more than 1-2 inches wider and deeper than the plant's root ball.
2. Add enough Miracle-Gro® Moisture Control® Potting Mix, which helps protect from both overwatering and underwatering, to the container so that the top of the root ball sits 1 inch below the rim. 
3. Gently remove the plant from its plastic pot and set it in the container.
4. Fill in around the root ball with more potting mix.
5. Water well after planting.

Caring for Hibiscus

Watering: All hibiscus plants need to be watered thoroughly every couple of days for the first few weeks after planting.

• Perennial hibiscus: After the first few weeks, water perennial hibiscus twice weekly for the first growing season. During the second growing season and beyond, water once per week unless it rains several days in a row. It's almost impossible to overwater these plants.
• Tropical Hibiscus: Tropical hibiscus plants should be kept consistently moist, so water whenever the top inch of soil is dry. (Stick your finger in the soil to check.) Containers may need to be watered 3 to 4 times weekly at the beginning of the summer and daily toward the end of the summer as the plants grow. The amount of watering you have to do will be less in cooler months.
• Rose of Sharon: Rose of Sharon is drought tolerant once established. While they love hot weather, these hibiscus still need water, just less frequently and more deeply than their perennial and tropical cousins.

Feeding: We talked about the importance of great soil above, but you'll get the most amazing garden results by adding the power of just the right plant food to your growing plan. Beginning a month after planting, feed any hibiscus regularly with Miracle-Gro® Water Soluble Bloom Booster® Flower Food, which was specially developed to encourage lots of colorful blooms. Using the Miracle-Gro® Garden Feeder makes feeding super-easy, but you can also mix the food in a watering can instead if you prefer. Either way, be sure to follow label directions.

Pruning: Tropical, perennial, and Rose of Sharon hibiscus require different pruning techniques for the best blooming season.

• Tropical Hibiscus: Keep plants tidy by snapping off flowers immediately after they fade. That will also encourage plants to continue pumping out blooms. Tropical hibiscus plants can be lightly pruned during the summer when they are actively growing to help control size and shape.
• Perennial Hibiscus: Wait until new sprouts emerge from the soil in the spring before you cut back the stalks from the previous year's growth. To encourage a large second flush of blooms during the summer, cut the new plants back by 1/3 after the first bloom. Do not cut plants back to the ground during the winter.
• Rose of Sharon: Pruning Rose of Sharon is similar to most woody trees or shrubs. Cut plants back in late winter or early spring to maintain shape and overall size. Never remove more than 1/3 of the plant's total size in a single year.

Propagating Hibiscus

While you can grow hardy hibiscus from seed, the best method for growing new perennial, tropical, or Rose of Sharon hibiscus plants is by using a stem cutting.

1. Prepare a pot with a drainage hole by filling it with a well-draining soil, like Miracle-Gro® Seed Starting Potting Mix (this mix is also great for stem and root cuttings). Water the soil and make a hole in the center using a pencil or your finger.
2. Using sharp, clean pruners or shears, cut a 6-inch stem from your hibiscus. You want to use new growth, so it's best to take your cutting in spring or early summer (mid-summer is best for Rose of Sharon). Also look for new, healthy leaves on your cutting.
3. Remove the leaves from the bottom half of the stem, and leave the top leaves alone.
4. Apply a rooting hormone to the bottom of the stem.
5. Gently place the cutting in the soil and cover with a plastic bag or dome. This helps keep the soil and air around the plant moist for better growth.
6. Place in a warm spot indoors with plenty of indirect light. Water regularly.
7. Watch for new leaf growth. Gently tug the stem to test for rooting (you'll feel resistance once the plant has rooted). Rooting can take anywhere from one to two months or more.
8. Once your hibiscus has rooted, you can move it to a bigger pot to continue growing. It's best to give it more time indoors to grow stronger before transplanting outside.

Propagating hibiscus can be tricky, especially on the first try. Start out with several stem cuttings. If you have more surviving plants than you have space for, give them to friends and family!

Overwintering Tropical Hibiscus Indoors

Gardeners in cooler climates will have to bring tropical hibiscus plants indoors during the winter. Before doing so, trim each plant back by about 1/3. Thoroughly wash off the stems and leaves to remove any lingering insect pests, then place plants in a warm location with lots of indirect light. This is a rest period for the plants, so allow the soil to almost fully dry out between waterings. Plants will likely drop their leaves. This is normal, and they will eventually grow out again.

With proper care and attention, your hibiscus will reward you with vibrant blooms, bringing beauty and a tropical touch to your garden or home.