Linaria

( lye - NAY - ree - uh )

At-A-Glance Information

Linaria, or Toadflax, is a genus of herbaceous flowering plants that have blooms reminiscent of Antirrhinum (Snapdragon). They require full sun or light shade and regular water, and their flowers will attract butterflies to your garden. Leaves are narrow and green, and flowers come in a variety of colors. These beautiful flowers are considered easy to grow and are best when massed together, as individual plants can get a bit leggy and wispy. Use Linaria in mixed beds, in containers, or as mid-height plants in floral installations.

Linaria Species and Varietals

The genus Linaria is a member of the Plantain plant family (Plantaginaceae), and includes 200 distinct species. Plants in this genus are closely related to those in Antirrhinum (Snapdragon) and Digitalis (Foxglove). Toadflax grows best in USDA hardiness zones 2-10. To find your zone, click here: Zone Map.

Linaria alpina (Alpine Toadflax, Mountain Linaria)
This species is native to mountainous regions of southern and central Europe and grows well in USDA hardiness zones 4-9. They are early colonizers of glacial moraine landscapes, and produce purple flowers with orange lobes towards the center of blooms. Individual plants reach up to between 12 and 18 inches tall when mature and in bloom.

Linaria bipartita (Clovenlip Toadflax, Cloven-Lip Toadflax, Cloven-Flowered Toadflax, Split Lip Toadflax)
This species is native to Morocco and is cultivated as an annual garden ornamental. Flowers are reddish-purple in the straight species, but color varies depending on the cultivar grown, and includes white (pictured). This species can reach up to between 4 and 12 inches tall at maturity when in bloom. This species is considered weedy or invasive in the United States (Alabama, Arizona, California, New Jersey, and Virginia), Germany, Québec, and South Africa.

Linaria dalmatica (Balkan Toadflax, Broadleaf Toadflax, Dalmatian Toadflax, Wild Snapdragon)
These plants produce unique flowers that are yellow with orange centers. These plants are commonly grown as garden ornamentals, and is also considered a noxious weed in many areas. Flowers bloom from spring through summertime. Individual plants can reach up to 2 to 4 feet tall when mature and in bloom. They are native to Eurasia, and grow well in USDA hardiness zones 3-10. This species is considered highly invasive in North America, South Africa, Argentina, and Australia.

Linaria spp. Hybrids and Cultivars
This group of flowers reach up to a foot tall and 6 to 8 inches wide at maturity. Leaves are green to blue-green. Flowers appear in clusters from spring through summer and come in a variety of colors, including blue with a yellow throat, magenta, pink, yellow and white. Cultivars are listed below:

'Cordoba'

'Enchantment'

'Fairy Bouquet'

'Licilia Azure'

'Licilia Peach'

'Licilia Violet'

'Northern Lights'

'Rhythm & Blues'

Linaria maroccana (Baby Snapdragon, Toadflax, Annual Toadflax)
This species of Linaria is an annual hailing from Morocco that reaches 1.5-2 feet tall and 6 inches wide. Flowers bloom in summer in red/gold, mauve, rose, pink, chamois, blue, purple, and violet. They are often blotched with a different shade at the top, and also come in bicolored shades. Sow seeds in early spring. This species is considered invasive in the western and eastern regions of the United States as well as Canada and Alaska.

Linaria purpurea (Purple Toadflax)
This species is native to Italy and is commonly cultivated as a garden ornamental around the world. It is considered a weed in some areas of the globe. They reach between 12 and 28 inches tall when in bloom, and produce light to medium purple flowers. Cultivars include 'Canon J. Went' (pale pink flowers), 'Springside White' (with white blooms and grey-green foliage), and 'Alba' (with tall spikes of airy white blooms). Considered weedy but not invasive; grows well in USDA hardiness zones 5-9.

Linaria reticulata (Purple-Net Toadflax, Netted Toadflax, Spurred Snapdragon)
This annual is native to Portugal and North Africa and grows well in USDA hardiness zones 2-11. Plants are 2-4 foot tall and 10 inches wide. Purple and orange flowers bloom in summertime. Leaves are very narrow and blue-green. Varieties include 'Flamenco' (1-1.5 feet tall with yellow flowers blotched with maroon), 'Flaming Passion' (16 inches tall and 8 inches wide with red flowers centered in yellow), and 'Aureo-Purpurea' (with deep purple to violet blooms).

Linaria vulgaris (Common Toadflax, Yellow Toadflax, Butter-and-Eggs, Brideweed, Jacob's Ladder, Wild Snapdragon)
This species is native to Europe, Siberia and central Asia, and has been introduced to North America. These perennials have short, spreading roots and blue-green leaves. Flowers are pale yellow and orange, and are typically pollinated by bumblebees. This species is considered highly invasive in Canada, Alaska, and the lower 48 states of the U.S.

Caring for Linaria

Plant Linaria in a space in the landscape that receives full sun. Ideally, these plants prefer to get between 6 and 8 hours of sun each day, with some afternoon shade in warmer climates. They will thrive in well-draining (typically rocky or sandy), moderately fertile soils with a pH of between 6.5 and 7.2 (slightly acidic to neutral). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Mulch around the planting area to increase soil moisture retention, suppress weed growth, and manage soil temperature fluctuations. Water new plants regularly to help them develop a strong root system. At maturity, Linaria are considered somewhat drought-tolerant, able to get by on rainwater alone with some supplemental waterings in the warmest months of the year. For the best performance, irrigate when the top two inches of soil feels dry to the touch.

Fertilize yearly in early springtime with a application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing and flowering seasons. Pruning Linaria is simple: remove spent blooms and any unsightly foliage. These plants bounce back well from pruning. Late in the season, plants can have a tendency to get leggy, especially if they are grown in too much shade. Plants can be cut down to about four inches tall at this point, and a flush of new growth and flowering will be triggered. There are both annual and perennial species of Toadflax. Annuals are typically dug up and composted at the end of the growing season, or can be left in place to enrich the soil. Perennial species can survive for between 2 and 5 years in most cases, and are then replaced. Both annual and perennial species will freely re-seed in the garden, providing new flowers for the landscape indefinitely.

Propagation

Linaria, or Toadflax, can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your Linaria plant, follow the instructions below:

Propagating Linaria by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 3-4 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new flowers.

Propagating Linaria by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed pods on these flowers readily release seeds when dried. Cut the whole flower spike off of the plant and place them in a container or paper bag. This will keep the seeds contained as you harvest more flower spikes. Once at a clean workspace, separate the seeds from the plant parts. They are very tiny, so take care when handling them.
In late summertime or early springtime, water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 14 to 21 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Linaria by Division
This type of propagation is relatively simple, but can only be done with perennial species; you will need a clean shovel, mulch, fresh soil, compost and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in very early spring (after the plant has entered dormancy, but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance. To propagate by division, follow these steps:

Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the root(s). Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick root section attached.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it sprout in the next growing season.

Linaria seed capsules are brown and round, containing dozens of seeds.

Linaria seeds are small, winged and brown to black. They are wind dispersed.

Problems and Pests

Certain species of Linaria are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Linaria, or Toadflax, can be susceptible to developing problems with the following pests and diseases in the landscape: