How much sun does Herbwilliam need?

Herbwilliam grows best in part sun conditions.

When does Herbwilliam bloom?

Herbwilliam blooms in June, July, and August.

Where is Herbwilliam native?

Herbwilliam (Ptilimnium capillaceum) is native to AL, AR, CT, DE and 18 more states, per vouchered herbarium specimen records and regional native plant society lists.

What pollinators does Herbwilliam attract?

Herbwilliam draws bees, beetles, and flies.

Is Herbwilliam HOA-friendly?

Herbwilliam takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Herbwilliam

Name: Pollinator Patch
Author: Pollinator Patch

Ptilimnium capillaceum

Last reviewed: August 2026

Toxicity unknown

Herbwilliam (Ptilimnium capillaceum) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

Light

part sun

Water

medium

Size

12"–24" H × 6"–12" W

Bloom

Jun, Jul, Aug

Native to

AL, AR, CT, DE and 18 more states

Pollinators

bees, beetles, flies

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Browse plants for this ecoregion

Cross Timbers Texas Blackland Prairies East Central Texas Plains Western Gulf Coastal Plain South Central Plains Eastern Temperate Forests Piedmont Northeastern Coastal Zone Middle Atlantic Coastal Plain Northern Piedmont Southeastern Plains Ridge and Valley Interior Plateau Mississippi Alluvial Plain Mississippi Valley Loess Plains Southern Coastal Plain Southern Florida Coastal Plain Atlantic Coastal Pine Barrens

Mock bishop's weed is a delicate annual wildflower with feathery, thread-like foliage and small white flowers arranged in flat-topped clusters. It grows in a compact, upright form and blooms throughout the summer months. This native plant thrives in partial sun with moderate moisture.

In an HOA neighborhood

Herbwilliam takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

Fine foliage can appear weedy or unkempt
Annual nature means gaps in planting each year
Small size and delicate appearance may look like volunteer weed

Wildlife value

The small white flowers attract a variety of beneficial insects including native bees, beetles, and flies. Its summer-long bloom period provides consistent nectar sources for pollinators.

Common questions

How much sun does Herbwilliam need?: Herbwilliam grows best in part sun conditions.
When does Herbwilliam bloom?: Herbwilliam blooms in June, July, and August.
Where is Herbwilliam native?: Herbwilliam (Ptilimnium capillaceum) is native to AL, AR, CT, DE and 18 more states, per vouchered herbarium specimen records and regional native plant society lists.
What pollinators does Herbwilliam attract?: Herbwilliam draws bees, beetles, and flies.
Is Herbwilliam HOA-friendly?: Herbwilliam takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Native range data from vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

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