How to Build a Small Garden Pond from a Container (Step by Step)
Just like regular garden ponds, your own small container pond can still be extremely aesthetic, beneficial and satisfying to create, but without the extravagant price tag or space requirements. Particularly in urban settings, container ponds can really serve as a boon to various insects and wildlife, like dragonflies, butterflies, birds, newts, and frogs that would otherwise struggle to find a suitable habitat and resources in these areas.
You’ll also have the opportunity to discover how small areas can develop into intricate, dynamic micro-ecosystems. In nature, micro-ecosystems can be found in things like rotting logs, puddles of water in tree hollows, or even on other plants. Truly, each of these micro-ecosystems are of vital importance, supporting a unique array of natural processes and organisms that would not otherwise be able to survive. Though it may sound silly, your container pond can serve much the same function!
How to Create a Small Garden Container Pond
1) Choose the Right Container
Container ponds can be made from barrels cut in half, buckets, livestock watering troughs, large plant pots, bowls, or really anything else that you can think of. The type of container that you use depends on the size and shape of pond that you want – the larger the container, the more creative freedom that you’ll have with the amount and species of plants you can have.
Material is something that you’ll also want to pay close attention to. Absolutely do not use any containers made with plastic that contains PFAS (polyfluorinated compounds), as these leach into water and any organisms in that water over time, causing a host of health and environmental issues. BPAs (Bisphenol A) should also be avoided, as this similarly leaches harmful chemicals.
For ease of use and maximum convenience, we recommend the types of pre-made containers below, as they’re designed specifically for mini-ponds like this:
Ceramic, fiberglass, non-porous stone like granite, and metals (such as aluminum, steel, brass, and others) work best for container ponds, as they won’t break down over time like plastic. Clean the container thoroughly before use, and incorporate a small liner if it’s not totally waterproof. If holes are present, such as drainage holes in planting pots, plug them with water-safe sealant.
2) Position for Adequate Sunlight
Your mini pond should be placed in an area that receives partial sunlight for at least 6 hours per day to ensure plant and water quality health. Keep in mind that you don’t want full sun, either, as such a small body of water will heat up very quickly. Do this, of course, before filling it with water.
Pay attention to which direction receives the most sunlight per day and try to find a suitable location for your container pond on that side, be it on a deck, patio, or outdoor table. Try to place wherever the pond can receive ample morning light, as this will be cooler and won’t scorch plants like the afternoon sun.
3) Add Suitable Substrate
Place an inch or two of aquarium grade gravel or similar water-safe substrate. The deeper and larger your container, the more substrate you can use. You can use just the gravel, or decrease to half an inch of gravel-like substrate with half an inch or so of soil, sand, or clay beneath for plants to dig roots into. Aquatic soil can also be used on its own, as this works well for providing nutrients to plant roots while also effectively holding them in place.
If you would like, bricks or stones can be placed in deeper containers to raise plants to the level that you prefer. To take up less space, you can also use plant support rings that attach to the sides of the container and will hold plants still in their planting containers at the appropriate depth in the pond.
4) Add Suitable Pond Plants
You’ll want plants to cover 25 to 75% of the container pond to ensure proper water filtration and oxygenation, particularly if you don’t want to use a pond pump or filter. Before planting, put a couple of inches of water into the container. If using tap water, let it sit for a couple of days so that it can neutralize, or treat it with dechlorinator as needed.
Space permitting, use a mixture of submerged plants, such as fanwort and anacharis, marginal plants like horsetail and cardinal flower, and floating plants such as water lettuce and dwarf water lily. This combination of plants will encourage adequate water oxygenation and filtration, shade the water so it doesn’t heat up from the sun as quickly, and such a dynamic mixture of plants will lend an interesting and vibrant aesthetic. If you have a container that’s large enough to house a few small fish (such as mosquito fish), these plants will also provide ample habitat for them.
Submerged plants should only be used if your container is a foot or more in depth, while marginal plants will require anywhere from a centimeter to several inches of standing water. Water hyacinth is a floating plant that’s suitable for most any sized pond, as it will grow to accommodate space – in container ponds, it will likely spread only a few inches, while in a large garden pond or lake it can spread up to a meter. Be sure to pay close attention to plant species’ needs and the size of your pond before purchasing them.
Submerged plants and marginal plants will need to have their roots secured either in the substrate or in pots. Floating plants can be placed atop the pond – if there’s an issue with them sinking at first or floating about too much, you can place them on bricks, stones, or a plant shelf to hold them in place until their roots develop and can help anchor them.
5) Finish Filling the Pond
Your container pond can be filled either with collected rainwater, as many sources urge due to its relative purity, or with tap water. In either case, test the water first using testing kits and treat as needed to obtain the desired pH level, water hardness, etc. and to remove harmful compounds such as ammonia and chlorine.
6) Create a Maintenance Routine
That’s about it! Your container pond is now ready! If your container is large enough to permit it, you can now add fish (see more below). To maintain your mini pond, trim plants back as needed, perform monthly 25 to 50% water changes (weekly, if fish are present), and regularly test water quality. In the winter, you will likely need to move your container pond indoors to protect it from the cold and snow.
Small Container Pond Considerations (Q & A)
Do I need a Pump & Filter for Container Pond?
Due to their small size, it is not usually necessary to have a pump or filter for container ponds, particularly if they only contain plants. However, depending on the size of your container pond, you can incorporate a small sponge filter to collect coarse particulate matter if you notice that your water is cloudy. Typically, though, simply incorporating some small plants into your mini pond is enough to keep the water clean.
Container ponds, or any pond for that matter, can become a magnet for mosquitoes and biting flies that rely on water for reproduction and larval development. To help deter these, you can incorporate a small solar powered pump to provide some aeration and water movement to prevent stagnation and algal growth, at no added running cost. You’ll need to be aware of what plants are in your pond if using one of these, though – some plants, like the floating fern, have delicate foliage that does not do well with water movement.
Can I have Fish in a Mini Container Pond?
Due to the small size of container ponds, it’s easy for a nutrient overload to occur, potentially leading to excessive algae growth, smelly water, and plant death. Fish produce a great deal of waste, both via their excrement and any uneaten food that remains in the water, so it’s generally not advised to have them in mini ponds as they may suffer from poor water quality, low dissolved oxygen levels, and potentially stagnant conditions in such a small space.
However, if your container pond is 50 gallons or greater, you may be able to have a few small fish so long as you run a small pump, such as the solar pump or sponge pump mentioned above, and are able to perform partial (25 to 50%) water changes once per week.
Without fish, these water changes will only be necessary every month or two. Small fish that can be suitable for container ponds if conditions are right include mosquito fish, Japanese rice fish, guppies, and southern platys, all of which typically grow to less than 2.5 inches in size. These fish may also be beneficial to ponds by eating algae and helping to keep plants naturally trimmed back via browsing. Mosquito fish are particularly well known for their propensity to eat mosquito larvae.