How to Grow Flax
That plant is flax – a joy to the gardener and the basic ingredient of linseed oil, linseed cake, flaxseed and of course, linen. With so many uses, it might be surprising to find out that flax is a tough little plant and also one of the easier plants to sow in the garden. Native to hot, sunny environments with poor soil (including species in much of the western and mid-western United States), the glaucous, delicate petals do not last long after blooming but are continuously replaced by new flowers. If you succession-sow your seeds, you can stretch the season from summer through till autumn.
American Meadows sells seed of two of the most popular species, Blue flax (Linum perenne ‘Lewisii’) and Scarlet flax (Linum grandiflorum ‘Rubrum’). Blue flax is a short-lived perennial, scarlet flax, an annual. Both seed prolifically and so are likely to stay in your garden for many years – particularly if you save seed and give Mother Nature a helping hand every once and awhile.
When & Where to Plant Flax
Flax should be planted in the early spring, but may also be planted in the late summer/early fall in temperate climates. Choose a sunny site with well-drained, sandy soil.Direct planting is preferred, but seeds can be sown in flats to be transplanted later. Start seeds indoors 6-8 weeks before the last frost. If you are sowing inside, be advised that flax resent root disturbance. To avoid problems, transplant them to larger pots before seedlings show major root development or become root bound.
Light: A full sun site is preferred.
Soil: Average to sandy well-drained soils are preferred. Flax does not do well in heavy clay or in wet conditions.
If direct seeding, rake soil and broadcast seeds, raking in and tamping down to make good soil to seed contact. Water in thoroughly.
Spacing: Flax spreads and naturalizes over time through seed dispersal.
Planting: You may plant flax in the early spring or in temperate climates, in the late summer/early fall to overwinter. Flax is a hardy plant and will not be harmed by late frosts in the spring.
How to Grow Flax Throughout the Season
Growth Habit: Flax gives a delicate, wild look to garden beds and meadows and grows anywhere from 15-30’ depending on species and conditions. It complements stronger foliage plants with its wispy stems of gray-green foliage. Each flowering stem is topped with silky short-lived disk flowers that bloom and are quickly replaced with more. Scarlet flax has gorgeous red petals with a dark eye – blue flax is a gentle, cornflower blue that gives a cool, relaxed look to plantings. Both bloom from mid-spring through summer, but succession sowing can give you a longer season.
Staking: Flax is not staked but its fairly spindly stems are helped with a bit of casual support either from stronger companion plants or from pea-sticks (dead, branched stems). Insert the pea sticks here and there around the developing plants to give them something to lean against and eventually mask.
Watering: Keep seeds and seedlings evenly moist. As plants develop they will need less water. If indirectly sowing indoors, allow sufficient ventilation as young seedlings can be killed by damping off disease if kept too wet and humid.
Fertilizing: No extra fertilizing is necessary.
Trimming & Pruning: Both annual and perennial flax will continue to bloom well if they are cut back by half after the first flush of bloom. If you live in a hotter climate, this can negatively affect the possibility of re-bloom.
Mulching: A very light top-dressing of compost can be given in the fall to blue flax, but deep mulching is not recommended. Mulching flax too deeply in the fall may result in lack of germination of new seeds in the following spring for both blue and scarlet flax.
Flax: End of Season Care
Dividing & Transplanting: Flax is not normally divided and resents root disturbance. Instead, gather seeds in the late summer and broadcast them where you want new plants – either in the fall or in the spring of the next season.
Overwintering: No special needs.
Pests/ Disease: Seedlings can be eaten by slugs and sometimes by birds. Monitor daily and if this seems to be a problem, set beer traps down in the evening or cover seedlings with light netting until established.
Flax: Extra Info
Companion Plants: Scarlet flax is lovely paired with the blue of another vigorous self-seeder – nigella. It is a wonderful choice for dry meadows as well as along the sides of a long driveway paired with ox-eye daisies – as is blue flax.
I have a few plants near the rocky base of my rain barrels, softening an otherwise utilitarian area and beautifully contrasting with self-sown California poppies. I never planted either right there – they found their own way from other sowings nearby.
The light airy nature of flax makes it an excellent choice for a cottage garden, near the front of the border or the edge of a pathway, where the delicate flowers can be appreciated. In warmer climates, consider it paired with Texas bluebonnet for a wildflower-lover’s symphony.
Additional Uses: Flax has numerous other uses besides being a beautiful plant for the meadow, cottage or informal garden and an attractor of insect pollinators. The seeds have become very popular in recent years, used as a fiber and protein supplement.
Linseed oil is made from these seeds and for centuries has been used to mix paints or protect wood. When this oil is made, the leftover vegetative matter is pressed into a cake and used to feed animals. And of course there is linen – the delicate, ancient cloth still used today made from the fine, long fibers.