Your carpet provides the perfect environment for mold to grow, as it contains organic fibers that can hold on to water for an extended period of time. Mold and mildew growth can be a serious health concern and can aggravate respiratory conditions that you may have, such as asthma. However, it can be hard to initially determine if your carpet has begun to grow mold, which means that you should know what signs to look for to determine when you should call a carpet cleaning specialist for your carpeting.