Pineapple Weed

Biology of Pineapple Weed

Pineapple weed (Matricaria matricariodies) is a common weed in the United States, adaptable as a summer or winter annual. It thrives in both high- and low-maintenance turfgrass lawns, landscapes, and nursery crops. Its tolerance for low mowing heights and compacted soils allows it to compete effectively in weak turf areas.

Identification and Growth Habits

This weed can appear as a summer or winter annual broadleaf in various turf settings. It exhibits a low-growing, bushy, branching habit and reproduces through seeds. These seeds can emerge year-round under favorable conditions. Seedlings typically germinate from late summer to early fall and again in early spring. Young plants form a dense rosette of fragrant, hairless, shiny green leaves. These rosettes emerge from a shallow taproot with a secondary fibrous system. As pineapple weed matures, its smooth stems elongate, adopting an erect or spreading habit. The leaves are fleshy, pinnately divided with deep lobes. When damaged or crushed, all parts of the plant emit a sweet pineapple-like scent. The flowers, blooming from May to September, are yellow, egg-shaped, and emit a similar fragrance. This weed can be distinguished from wild chamomile by its sweet scent, as chamomile ranges from bitter to odorless.