[header] How to keep soil moist [title] Mix organic compost into your soil. [step] Compost will also improve soil drainage and water retention, as well as improve the overall nutrient composition of the soil. Spread handfuls of the material over the surface of the soil, then use a till or a pitchfork and mix the compost with your existing soil. 
Organic compost is most useful in yards or garden beds, rather than potted plants. [substeps] Conventional organic compost will have a ph level of around 7 and contains nutrients that will strengthen your soil.