How to Drill Drainage Holes in Fiberglass Planters

One key difference between indoor and outdoor planters is whether or not they have drainage holes. Typically, indoor fiberglass planters will be sealed, and outdoor planters will have drainage holes that allow water to seep out; both to avoid flooding a plant’s root structure and to protect the planter’s overall integrity. However, if you ordered a sealed planter and now need it to have drainage holes, here are step-by-step directions on how to drill holes in fiberglass planters.

Materials Needed:

  • Eye protection
  • Safety mask
  • Drill
  • 1 inch spade drill bit
  • Wet/Dry Vacuum

How to drill holes in fiberglass planters:

  1. Place planter upright on a flat surface, and ensure the surface where you are drilling is protected. Do not flip the planter upside-down to drill holes, especially if it is painted as it might damage the finish.
  2. Mark where you’d like drainage holes in the planter interior. We typically recommend a minimum of two drainage holes. However, the total number of needed drainage holes will vary based on the size of the planter.
  3. After marking your interior drainage hole locations, make sure that any holes drilled will not go through the “feet” of the planter.
  4. Place the drill bit on the mark, and push the drill forward slowly and evenly until you’ve reached through the other side.
  5. Use a wet/dry vacuum to clear away any debris.
Showing what a drainage hole in a fiberglass planter looks like

A few notes:

  • Use a ½ inch spade drill bit for smaller planter sizes.
  • A good rule of thumb for the number of drainage holes needed is 3-4 holes for 36 inch planters, and 4-6 holes for 46 inch planters. However, consider the overall planter width and height before drilling. For example, though we recommend 4-6 drainage holes for a 46 inch planter, it might not be feasible to include that many drainage holes in a tall, skinny 46 inch planter.

Drilling drainage holes in a small number of fiberglass planters likely won’t take up too much time. However, for larger planter quantities you’ll save significant time by placing an order and selecting the “add drainage hole” option.

Allison is a budding plant person looking to share what she learns from horticulture and other subject matter experts. She earned her Bachelor's degree in Public Relations from Anderson University and is a SEO and Outreach Specialist at NewPro Containers. Her experience in PR and marketing has given her the skills to distill key facts and advice clearly and concisely across various platforms and mediums. When she is not researching new plants to add to her growing collection, she enjoys going on motorcycle rides and watching road-trip movies.

Fiberglass Planters

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