The answer to 'why is my garden drainage problems' is that poor drainage in a garden can be caused by a variety of factors, including soil composition, the slope of the land, and improper drainage systems. Symptoms of poor drainage include standing water, soggy soil, and the growth of moss or weeds.
Some common causes of garden drainage issues include heavy clay soils that don't allow water to percolate, a flat or low-lying landscape that doesn't allow water to flow away, and clogged or damaged drainage pipes or channels. Solutions can include adding organic matter to improve soil composition, installing French drains or swales to redirect water flow, and ensuring proper grading and slope to facilitate drainage.