How to Grow Blackberry Lily

Blackberry Lily

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Blackberry lily (also sometimes called leopard lily) is actually a species of Iris rather than a lily. It is a clump-forming plant that grows from spreading rhizomes, with strap-like leaves up to 10 inches long. In early to mid-summer, wiry stems shoot up as much as 4 feet, with bright orange, red-spotted flowers with six petals, The flowers give way to pear-shaped seed pods which open in late summer to reveal blackberry-like seed clusters (the source of the common name).

Blackberry lily is a fairly short-lived perennial, but its rhizomes will spread gradually to sustain the plant in the garden. And it will also self-seed, creating an ongoing colony of plants.

Blackberry lily is normally planted in the spring from potted nursery plants or bare roots purchased from online sellers. Bare roots will generally mature into flowering plants in their first season, though it sometimes can take two seasons.

Botanical Name Iris domestica
Common Name Blackberry lily; leopard lily
Plant Type Herbaceous perennial
Mature Size 2–3 feet tall, 9–24 inches wide
Sun Exposure Full sun
Soil Type Well-drained
Soil pH 6.1 to 7.8 (slightly acidic to slightly alkaline)
Bloom Time Mid to late summer
Flower Color Orange with red spots
Hardiness Zones 5–10 (USDA)
Native Area India, China, Russia
Toxicity Mildly toxic to humans and animals
Iris domestica
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Blackberry Lily Fruits
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Blackberry Lilies
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Blackberry Lily Care

Blackberry lilies make fine companions for irises. That's because as a member of the iris family, they enjoy the same growing conditions: lots of sun, average moisture, and soil that drains easily. Blackberry lilies are not long-lived perennials, but they are easy to grow, and you can propagate them at home to keep the flowerbed populated with these unique orange and red speckled blooms.

Light

Choose a site with full sun to grow your blackberry lilies. A minimum of four hours a day is necessary for plant health and blooms, and six hours is even better.

Soil

Having the perfect soil isn't important for growing blackberry lilies, but having good drainage is. Soggy soils, especially in winter, can cause the rhizomes of blackberry lilies to rot. These plants are not fussy about soil pH; they will do well in both alkaline and acidic soil conditions.

Water

While blackberry lilies respond to regular watering by producing larger, healthier blooms, they are also drought tolerant. Dry winter soils are ideal. Err on the side of less water, not more.

Temperature and Humidity

Hot weather and high humidity are not issues for cultivating the blackberry lily. The plants are not susceptible to mildews or fungi, provided no standing water is present.

Fertilizer

Supplemental fertilizer is not necessary to grow blackberry lilies. The plants are not heavy feeders, and can get the nutrients they need from the soil.

Is Blackberry Lily Toxic?

All species of Iris are considered class 2 (minor toxins causing stomach and intestinal upset) and class 4 toxins (causing dermatitis reactions) for humans, according to official lists of poisonous plants. These plants are somewhat more toxic to dogs, cats, and other animals. The primary toxins are thought to be irisin and certain pentacyclic terpenoids.

Poisoning in humans is more common than you might think, since this plant has a long history of being used in folk medicine. People who consume the plant in this way without training may experience stomach upset.

Symptoms of Poisoning

In humans, consumption of plant parts, especially the roots, can cause diarrhea and vomiting. The plant is somewhat more toxic to animals, where ulcers of the stomach and small intestine have been known to occur. Though most symptoms are relatively minor and temporary, a seriously ill pet should be brought to a veterinarian. Treatment may include induced vomiting, and treatment with activated charcoal to absorb the toxins. Most often, though, symptoms are mild and quite temporary.

Blackberry Lily Varieties

In addition to the pure species, there are two named cultivars commonly grown:

  • 'Hello Yellow': This is a dwarf cultivar with leaves growing only 10 inches tall. The flower spikes rise to 20 inches, topped with unspotted, butter-yellow flowers.
  • 'Freckle Face': This is a more prolifically blooming version of the species plant, producing as many as 12 blossoms per plant.

Blackberry Lily vs. Tiger Lily

The similar name and appearance of the tiger lily (Lilium lancifolium) and the blackberry lily can cause confusion amongst gardeners. At a glance, one simply notices similar orange petals with darker spots on both flowers. However, the tiger lily—a true lily—is quite different when you look beyond surface appearances. Start with the root structure: The tiger lily produces non-tunicate bulbs with layers of scales attached to a basal plate, while blackberry lily grows from fleshy rhizomes that look like swollen roots. Tiger lilies can grow several feet tall, and are hardier than blackberry lilies, down to zone 3, while the much smaller blackberry lily is sometimes questionable even in zone 5. Tiger lily also has flowers with prominent stamens and recurved petals, missing from the blackberry lily.

Pruning

Although blackberry lily does not require "pruning" in the formal sense, removing the seed capsules as they form will prevent them from ripening and casting seeds into the garden, where you will need to pluck the volunteers. And at the end of the growing season, remove the yellowing foliage to tidy up the garden and eliminate fungal spores and nesting areas for pests.

Propagating Blackberry Lily

Similar to the way that iris or daylily rhizomes can be divided, you can propagate blackberry lilies in the same way—by digging and dividing the root clumps. This is best done when the flowering is over and the plants are mostly done growing. Dig up plants, and use a sharp knife to cut apart pieces that have a fan of foliage attached. Replant them in the desired locations at the same depth.

Periodic division is also a good time to inspect the roots for borers and cut away any diseased or rotting sections.

Growing Blackberry Lily From Seed

Blackberry lily can be grown from seeds, but it is a little trickier than it is for other types of iris. The seeds will germinate best if they receive a period of cold stratification before planting. Commercial seed companies usually chill the seeds before shipping, but it's still a good idea to store the seeds in a refrigerator for several weeks before you sow them.

Sow the seeds indoors in mid to late winter in a seed starting mix, barely covering them with 1/4 inch of mix. Keep the pots well-watered in a bright location until the seedlings sprout. Continue to grow them in a bright location, watering when the soil gets dry. When the weather warms in the spring, move the pots outdoors and continue to grow them until they are well established. At this point, they can be transplanted into the garden.

If you so seeds directly in the garden, do it in late fall or early spring, as soon as the ground can be worked. Fall-sown seeds may flower in the first year, but seeds sown in the spring will probably not flower until the second year.

Potting and Repotting Blackberry Lily

Growing blackberry lilies in containers is a great way to "stage" the plants when they come into bloom: Before blooming, place the containers in an out-of-the-way spot, as the foliage is not much to look at. When the blooms begin, move the containers to a prominent spot on the porch or patio where you can enjoy the flowers.

Plant up two or three blackberry lilies in the same pot to give a full look. Use well-drained potting soil. Arrange the rhizomes close to the soil's surface so that they are not touching. Divide and repot the lilies as they expand and become crowded. Repot in late summer, when growth slows down.

In cold climates (freezing temperatures and snowfall), the dormant plants in their pots can usually be stored in a sheltered but cool area for the winter. Zone 5 gardeners, however, may find that potted blackberry lilies perish over the winter unless moved into a garage or basement.

Common Pests/ Diseases

Blackberry lilies are generally trouble-free plants. However, the common iris borer can infect and even kill plants. The pest is insidious and may leave no signs at first except an entry hole at the base of the plant. If your plant looks wilted or discolored, look for this hole. Remove and destroy any infected plants, roots and all. Root sections can be salvaged by closely inspecting them and cutting away any rotting sections or areas with borer holes.

Orange Tiger Lilies
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