Getting it to bloom

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

Also called Porcupine grass, Banded miscanthus, Striped eulalia (Miscanthus sinensis 'Strictus').

More about porcupine grass

About Porcupine Grass

Miscanthus sinensis 'Strictus' · also called Porcupine grass, Banded miscanthus · flowering

Miscanthus sinensis 'Strictus' is a bold, stiffly upright ornamental grass cultivar of the Chinese silver grass species, prized for its distinctive horizontal yellow-cream banding across the arching green leaf blades — a feature unique among upright miscanthus forms. In mid to late autumn it produces airy, pinkish-copper plume panicles that age to silvery-white and persist attractively through winter. The critical care point is full sun — without sufficient light, the characteristic yellow banding fades to plain green. It holds the RHS Award of Garden Merit. Miscanthus grasses are not listed as toxic by the ASPCA, but classified as mildly-toxic due to the potential for mechanical injury from sharp leaf edges and limited specific pet-safety data.

Plant type: flowering

The reasons porcupine grass isn't blooming

Almost every non-blooming porcupine 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 porcupine 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 porcupine grass to flower

Maximise sun. Give porcupine 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 porcupine grass and get the feeding right with the porcupine 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

Porcupine 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 porcupine grass care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Porcupine Grass blooming — frequently asked questions

Why won't my porcupine grass flower?

Porcupine 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 porcupine grass bloom?

Give porcupine 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 porcupine grass normally bloom?