The plants beside a pond are part of its design, not just a backdrop. Mature roots, spreading runners, falling leaves, and access for maintenance can all affect the feature over time. A tree or grass is not automatically unsafe because it has roots, and there is no single planting distance that fits every species and pond. Plan around the plant's mature size and the pond's liner and plumbing layout.
Watch for plants that spread underground
Some bamboos and spreading ornamental grasses can travel beyond their original planting area. Identify the exact species or cultivar before planting and check how it spreads in your climate. Consider how you will contain or maintain it without digging into a liner edge, pipe, or cable. Do not assume that a plant sold as an ornamental will stay in the space shown on its tag.
Give trees room to mature
Willows and other moisture-loving trees can develop extensive root systems and substantial canopies. Roots can change soil conditions around a pond edge or complicate future repairs; leaves and branches add debris. The right setback depends on the species, mature size, soil, and how the water feature was built. A qualified landscape or pond professional can help assess a planting near an existing liner rather than relying on a universal number of feet.
Keep the edge accessible
Leave space to inspect the waterline, remove leaves, reach the skimmer, and repair an edge if necessary. Mulch and soil should not be placed where they can wash into the water or hide a low liner edge. If you see persistent wet soil outside the pond, investigate the water-loss pattern before blaming a nearby root. See Is My Pond Losing Water to Evaporation or a Leak?.
Choose for the whole site
Match plants to light, soil moisture, mature spread, local rules, and the amount of pruning you can sustain. For plants that grow in the water itself, the considerations are different: read Pond Plants That Can Spread: What to Check Before Planting. If you are retrofitting an established pond, locate buried services before digging and avoid disturbing its liner and edging.