How to Grow and Care for Bear's Breeches

Bear's breeches, also called oyster plants or acanthus, are tall, eye-catching perennial plants with glossy green leaves and tall spikes of flowers. Bear's breeches are wide and commanding plants that need at least 3 to 4 feet of garden real estate each as they like to spread out. These plants thrive in full sun to partial shade and rich soil and are drought-resistant once established.

Bear's Breeches Care

Here are the main care requirements for growing bear's breeches:

• Plant bear's breeches in full sun to partial shade.
• Water the plant 1 inch per week once it's established.
• Use a rich, composting soil to plant bear's breeches.
• Protect the plants with mulch in the winter.

Warning

Bear's breeches is listed as an invasive species in Oregon and a few areas in California in the Invasive Plant Atlas of the United States.

Light

Plants will do best in full sun to partial shade. They need more protection in hot climates, but wherever you grow them, they need at least a few hours of sun to bloom well.

Soil

Bear’s breeches appreciate a rich soil with plenty of compost or other organic matter. Once established, they are more accommodating about poor soil but they need good drainage, especially in winter. Sitting in cold, wet soil can cause the roots to rot and may kill the plants.

Water

Once established, bear’s breeches are very drought-resistant, but perform best with regular watering. An inch a week should be plenty.

Temperature and Humidity

These plants are dependably hardy. Protect your plants during their first couple of winters with a thick layer of mulch. In zones 6 and lower, continue this practice for the life of your plants.

Fertilizer

Bear’s breeches are not heavy feeders. Start with rich soil and side dress annually with compost. You can use a balanced fertilizer in spring or midsummer if the plants look like they need it. For the amount to use, follow product label instructions.

Types of Bear's Breeches

• Acanthus balcanicus var. hungaricus, Hungarian bear's breeches: The most widely adaptable species, it blooms later and is less susceptible to late frosts.
• Acanthus mollis, common bear’s breeches: This is the most popular species, but it can also be the most temperamental about blooming, with buds being damaged by late spring frosts.
• Acanthus spinosus, spiny bear’s breeches: This is more adaptable than A. mollis and appears more thistle-like.

Pruning

Cut the plant back after flowering in hot climates to encourage fresh new foliage. Gardeners with cold winters should leave the plants standing and allow the leaves to protect the crown. Wait until you see new growth in the spring to cut back any damaged or declining leaves.

Propagating Bear's Breeches

Bear's breeches propagate very easily by themselves, but you can plan to get some of your own to transplant in early spring. They can be propagated by dividing the plants or taking root cuttings. Dividing the mature plants will keep them healthy and blooming at their best. Here's how:

1. Bear’s breeches have long tap roots and do not like to be moved. If you want to divide your plants, the best way to do it is to thrust a shovel into the base of the plant’s roots during the fall and leave the plant in place. (Wounding the taproot encourages the plant to send up plantlets.) The following spring, you should see several new baby plants that can easily be transplanted.
2. Dig up the new plants and be careful not to damage the roots of either the mother plant or plantlets. Separate any tangled roots with a sharp sterile knife.
3. Replant plantlets in a suitable growing site and water the soil until moist.
   

How to Grow Bear's Breeches From Seed

While this plant does grow from seed, it takes a long while to become established. The best time to start bear’s breeches from seed is the springtime. You can start the seeds indoors at any time or directly sow them in the spring by planting them in the desired location and watering them. It will take about 21 to 25 days before you see them germinate. Expect to wait several years for them to bloom. They need time to grow and establish their root system before they start to send out flower buds.

Potting and Repotting Bear's Breeches

These plants grow well in large pots or container gardens. Take some of the new plants from a division of the plants outside in the garden and plant them carefully in the pots filled with a mixture of potting soil and peat moss. Not only does this keep bear's breeches in a controlled area (the pot) but it makes for attractive foliage for the outside patio.

Overwintering

While the plant is still becoming established, you'll want to cover it with a thick layer of mulch in the winter. If attempting to grow in zone 6, you should do this for the entirety of the plant's life.

Common Pests & Plant Diseases

Insects don't bother bear's breeches except for slugs and snails that hide out and feed if the soil is damp. These pests can do substantial damage if left unchecked. Spraying them with a salt spray solution or using diatomaceous earth will get these pests under control.

The gorgeous leaves of bear's breeches are susceptible to a handful of diseases, with powdery mildew being the usual culprit, along with fungal and bacterial leaf spot diseases. Good air circulation and a dose of homemade fungicide will eliminate these issues.

How to Get Bear's Breeches to Bloom

Bloom Months

Bear's breeches typically bloom in late spring to midsummer. Once the plant begins to flower, expect to see blooms for three to four weeks.

What Do Bear's Breeches' Flowers Look and Smell Like?

Pink-mauve bracts surround the spikes of white flowers that resemble snapdragons. The foliage of this somewhat elaborate plant is a wide rosette of arching, shiny, dark green leaves that are deeply lobed. They are always touted as architectural plants, and their leaves are often used as a motif in moldings, reliefs, and even jewelry. Many gardeners grow them for their foliage alone, although the flowers are quite nice themselves and will attract butterflies and other pollinators.

How to Encourage More Blooms

To encourage bloom, the plants need a few hours of direct sun each day. While they are imposing and beautiful, they can be erratic, blooming well in one year and disappointing in another.

Deadheading Bear's Breeches' Flowers

Deadhead at the end of a season when the flowers fade.

Common Problems With Bear's Breeches

This plant is problem-free and the only real concern you will have is its aggressive growth. Before planting bear's breeches, make sure you want to keep the plant in your yard because it will be extremely difficult to remove and contain.

From: thespruce