A landscape design must be functional, as well as aesthetic. For those who have septic systems rather than sewer connections, there are steps you can take in your landscaping work to help maintain your septic systems' health.... Plan drainage in your landscaping so as to channel water away from septic systems. Keep trees 100 feet or more away from septic systems, lest invasive roots cause damage. Willow trees in particular are notorious for causing damage to septic tanks -- keep them even further away. Grass can be planted on your drainfield to fight erosion. To further explore these and other tips for septic tank health, please consult the septic system maintenance advice offered by About's Home Buying and Selling Guide, Janet Wickell.