Galium spp. can be either Annual to perennial seed weed. Galium aparine is an annual species germinating from spring to fall. Occurs mainly in fresh, nutrient-rich, humus-rich, deep loamy and clay soils that are well-supplied with moisture. With adequate nutrient-supply, this plant can be found on practically any soil, normally spreads into the field from field margins and hedgerows.
Cleavers [Galium Aparine]
Cotyledons are fleshy-rough, long-ovate, approx. 15 mm long, stalked, and with clear groove at the tip of the central vein (Picture 1). The leaves are lanceolate (spear shaped), relatively soft, usually dark-green arranged in groups of 6-9 in whorls around the nodes (Picture 2),. The leaf surface has (rough) forward-curving spikes making the plant rough to touch and sticking to most surfaces. The flowers are inconspicuous, white, floriferous panicles formed in the axils that extend beyond the petal. The seeds are 4-6 mm in size, round, dense, with hooked bristles arranged on heads (Picture 3). Each plant produces approx. 300-400 seeds that have been found to remain viable for 7 to 8 years in the soil. Germination temperature: 2- 13 °C.