Getting it to bloom

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

Also called Witchgrass, Tumble Panic Grass, Old Witch Grass (Panicum capillare).

More about witchgrass

About Witchgrass

Panicum capillare · also called Witchgrass, Tumble Panic Grass · flowering

Witchgrass is a native North American annual grass known for its enormous, delicate, hair-fine panicles that make up half the plant's volume at maturity. The panicles break off at the base in autumn, tumbling like tumbleweed and dispersing seed widely. Though often treated as a weed, it has ornamental value in wildflower meadows and naturalistic plantings.

Plant type: flowering

The reasons witchgrass isn't blooming

Almost every non-blooming witchgrass 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 witchgrass 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 witchgrass to flower

Maximise sun. Give witchgrass 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 witchgrass and get the feeding right with the witchgrass 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

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

Witchgrass blooming — frequently asked questions

Why won't my witchgrass flower?

Witchgrass 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 witchgrass bloom?

Give witchgrass 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 witchgrass normally bloom?