What Are Those White Spots on My Soil?

Is white stuff on my soil a pest?

Almost never — white fuzzy patches or a white crust are overwhelmingly either harmless surface mold (from overly moist soil) or a mineral salt buildup (from tap water or fertiliser), not insects. Pests are usually mobile, tiny, and specific in appearance (webs, cottony clumps that move).

How do I know if it's mold or mineral salt?

Mold is fuzzy, fluffy, or powdery in texture and appears after a period of overwatering or poor airflow. Mineral salt is a hard, crusty, often ring-shaped white deposit, usually around the rim of the pot or soil surface, from water evaporating and leaving minerals behind.

Is soil mold harmful to my plant?

Surface mold is mostly cosmetic and not directly harmful to the plant, but it's a signal the soil is staying too wet — which can lead to root rot if the underlying watering habit doesn't change.

How do I get rid of white mold on soil?

Scrape off the top layer, let the soil dry out more between waterings, and improve airflow around the plant (a fan or more space between pots helps). Persistent mold can also mean it's time to refresh the topsoil.

How do I get rid of mineral salt crust?

Scrape off the crusted layer, then flush the pot thoroughly with plain water (let it run through and drain fully) to dissolve and wash out built-up salts. Switching to filtered or rested tap water reduces future buildup.