Things Growing in Gutters

When a gutter system is neglected, it can become cluttered with debris that prevents water flowing to the downspouts. While most homeowners are aware of the importance of gutter cleaning, it’s understandable how easily this unpleasant chore can be put off until the situation becomes critical. But things growing in your gutter system will eventually lead to bigger problems that could be very costly to fix.


Because of all the rain Vancouver homes are exposed to, moss growth is a serious threat to your gutter system. Most often it starts with the roof. Depending on which way the house faces and how much direct sunlight it receives, some roofs are more prone to moss growth than others. Once moss starts to grow on the roofing tiles, rain washes spores into the gutters and downspouts, where it thrives in a damp environment. Moss is very absorbent; if left in the gutters, it can weigh gutter sections down to the point of sagging, misalignment, or even breaking away from the fascia.

Mold and Mildew

Mold and mildew are kinds of fungi that can appear in gutters. Mold typically is green or black in colour and grows on organic matter (food, leaves, pine cones); mildew tends to be grey or white, growing on damp surfaces. While the appearance of mold and mildew on roofs or in gutters is unsightly, these two types of fungi actually don’t damage to the roof or gutters. Mold, however, can pose a health threat depending on where in the gutter system it has manifested itself.

Plant Life

When gutters aren’t cleaned regularly, twig, leaves, pine cones, seed pods, etc. start to decompose. Add a little water and presto! you have a nutrient-rich canvas for plant life. Just as with moss, grasses, flowering plants, and weeds can add a significant amount of weight to a gutter system, especially during periods of continual rain.


If grass and plants can begin life in your gutters from airborne seeds, so can trees. Trees are especially happy near downspouts where their roots can develop vertically instead of horizontally. A tree growing in the gutters doesn’t just block water flow; as the tree grows bigger, roots push aluminum gutters out of shape and can punch holes in the mental, causing extensive damage.

Tips to prevent things growing in gutters include:

  • cleaning the gutters regularly
  • annually inspecting and cleaning the roof
  • trimming back trees growing near the house to minimize the amount of shade