Spotted spurge is a summer annual that depends on prolific seed production for survival. A single spurge plant can produce 1000s of seeds during the growing season. Seeds are small and can remain dormant for years until germination conditions are suitable.
Seeds produced in summer germinate readily while those produced in late fall will remain dormant until the following spring. Spotted spurge germinates best when temperatures are between 75° - 85°F, but germination can occur at temperatures as low as 60°F and as high as 100°F. When moisture is available, germination can occur from February - September in some areas.
Light is also required for maximum germination; seeds buried deeper than 1/2" will not germinate well. Plants germinating early in spring under cool conditions may remain as small seedlings until temperatures are more desirable for top growth.
Once the spurge seed germinates, a small rosette of leaves develops. As growth continues, leaves form a dense mat that can grow up to 3' in diameter.
Reproductive growth is rapid and seeds can be produced as soon as 5 weeks after germination.
Prevention is the primary method of managing spotted spurge. Once established it is difficult to control. Clean machinery (lawn mowers) and workers' clothing to remove any weed seeds that might be present.
Infested areas must be constantly monitored to cultivate or hand-pull new plants before they produce seed. Plants that are hand-pulled often break at the stem, leaving the root and several buds or a single stem from which re-growth is possible.
Pre-emergent herbicides are helpful in reducing establishment of spurge if they are applied in late winter before weed seeds germinate. Apply pre-emergent's before soil temperatures at the 1" depth go above 55° - 60°F.