Getting it to bloom

Why won't my Blue Lyme Grass bloom? (and how to make it flower)

Also called blue dune lyme grass, sand rye grass (Leymus arenarius 'Blue Dune').

More about blue lyme grass

About Blue Lyme Grass

Leymus arenarius 'Blue Dune' · also called blue dune lyme grass, sand rye grass · flowering

'Blue Dune' blue lyme grass is a tough, cool-season grass grown for its striking steel-blue, broad-bladed foliage and wheat-like flower spikes. A coastal dune native, it tolerates sand, salt, wind and drought superbly. Be warned: it spreads aggressively by rhizomes and can become invasive, so it is best contained in pots, barriers or where vigorous groundcover is wanted.

Plant type: flowering

Watch for — Flopping flower stems: Tall flowering stems can lean or splay, especially in rich soil; lean conditions and full sun improve posture, or shear flowers off.

The reasons blue lyme grass isn't blooming

Almost every non-blooming blue lyme grass traces back to one of these, roughly in order of how common they are:

Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
The plant has not been deadheaded, so it stops flowering once it sets seed.
Irregular watering — drought or waterlogging at the budding stage makes buds abort.
It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding blue lyme grass a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get blue lyme grass to flower

Maximise sun. Give blue lyme grass the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for blue lyme grass and get the feeding right with the blue lyme grass fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Blue Lyme Grass flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full blue lyme grass care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Blue Lyme Grass blooming — frequently asked questions

Why won't my blue lyme grass flower?

Blue Lyme Grass blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make blue lyme grass bloom?

Give blue lyme grass the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does blue lyme grass normally bloom?