Natural Swimming Pool: I Built One for $2,500 – Here's How

Ever dreamed of jumping into a cool, clear swimming hole without the red eyes and chlorine smell? You're not alone. I've been designing backyard landscapes for over a decade, and more people than ever are asking me about natural swimming pools. These aren't just fancy ponds — they're fully functional swimming spots that use plants and gravel to keep the water clean. And honestly, they're way easier to build than you think. Let's walk through everything you need to know about building natural swimming pools so you can start planning your own.

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• 1、What are Natural Swimming Pools?
• 2、Building Natural Swimming Pool Designs
• 3、Plants for a Natural Swimming Pool
• 4、Natural Swimming Pool Maintenance and Seasonal Care
• 5、Cost, Size, and Location: Planning Your Natural Pool
• 6、Common Misconceptions About Natural Swimming Pools
• 7、Water Quality and Health in Natural Pools
• 8、Wildlife and Biodiversity in Natural Pools
• 9、Advanced Building Tips for Natural Pools
• 10、Seasonal Adjustments and Troubleshooting
• 11、FAQs

Ever dreamed of jumping into a cool, clear swimming hole without the red eyes and chlorine smell? You are not alone. I've been designing backyard landscapes for over a decade, and more people than ever are asking me about natural swimming pools. These aren't just fancy ponds — they're fully functional swimming spots that use plants and gravel to keep the water clean. And honestly, they're way easier to build than you think. Let's walk through everything you need to know about building natural swimming pools so you can start planning your own.

What are Natural Swimming Pools?

The Two-Zone System: It's Not Just a Hole in the Ground

Natural swimming pools work with nature, not against it. Instead of dumping chemicals into the water, you build a self-cleaning ecosystem. It sounds complicated, but the concept is surprisingly simple — you split the pool into two zones.

When I sit down with clients to sketch out a natural swimming pool design, the first thing I explain is the two-zone system. The regeneration zone (about 50-60% of the total area) is where the plants and gravel live. This is the filtration powerhouse. The other half is the swimming zone — your clean, open water for splashing around. Here's the key: water circulates between these two zones constantly. A small pump pushes water from the swimming area into the plant zone, where roots and gravel trap debris and consume nutrients. By the time the water cycles back, it's crystal clear. I've seen 300-square-foot systems keep water pristine for years with zero chemicals.

How Natural Filtration Really Works

You might think you need expensive filters and pumps, but natural pools rely on biology instead. The gravel in the regeneration zone provides surface area for billions of beneficial bacteria to live. These bacteria break down organic waste — think leaves, skin cells, and sunscreen — into harmless nutrients that the plants then eat.

Let me walk you through the process. When you take a dip in your natural swimming pool, you're introducing some organic matter into the water. The pump gently moves that water into the regeneration zone. As it passes through the gravel, beneficial bacteria get to work breaking down the waste. The plant roots absorb the resulting nutrients, and the water flows back to you clean and oxygenated. This cycle runs 24/7 without you lifting a finger. I remember helping a client in Arizona who was skeptical about the "no chemicals" promise. We installed a small skimmer and a pump rated for 1,500 gallons per hour. After six weeks, her water was clearer than her neighbor's chlorine pool. She called me to say she'd never go back. That's the power of a well-designed natural swimming pool.

Building Natural Swimming Pool Designs

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Liner vs. Clay vs. Concrete: Which One Should You Pick?

You've got options when it comes to containing the water. Building natural swimming pools typically involves choosing between a synthetic liner, clay, or concrete. Each one has trade-offs, and the right choice depends on your budget and how much digging you want to do.

In my experience, EPDM rubber liners are the sweet spot for most DIYers. They're flexible, last 20 to 30 years, and cost roughly $0.50 to $1.00 per square foot. RPE liners are similar but thinner and a bit cheaper, though they're harder to fold into complex shapes. Bentonite clay is the most natural option — you compact it into a 6-inch layer that swells when wet to seal the pool. It's incredibly eco-friendly, but it requires heavy machinery and precise installation. Concrete is durable and permanent, but it's expensive (around $3 to $5 per square foot) and can leach lime into the water, which affects pH. I usually tell clients that if you want a weekend project, go with EPDM. If you want to get your hands dirty and feel like a true homesteader, try clay. Concrete is best left to the pros.

Shape, Depth, and Slope: Getting the Basics Right

Don't overthink the shape. A simple rectangle with straight walls is the easiest and cheapest to build. But if you want something that feels like a natural pond, go with an irregular, dish-shaped design. The golden rule is a 1:3 slope — one foot vertical for every three feet horizontal.

You might be surprised at how shallow a natural swimming pool can be. Most people don't need a deep end. I usually recommend a maximum depth of 4 to 5 feet. That's deep enough to cool off and swim laps without the risk of diving accidents. Shallow water also warms up faster in the spring, which extends your swimming season. When you're excavating, make sure the edges are gradual. A sudden drop-off looks unnatural and can cause erosion. If you're using a liner, lay a layer of sand or old carpet underneath to protect against punctures from rocks. I once skipped the underlayment on a client's pool, and a sharp pebble poked a hole within a month. Trust me — take the extra hour to pad the floor. Your back will thank you later.

Plants for a Natural Swimming Pool

Oxygenators and Marginal Plants: The Real Heroes

Plants do the heavy lifting in a natural pool. They consume nutrients, shade the water to prevent algae, and release oxygen to keep the ecosystem balanced. Without them, your natural swimming pool design is just a muddy hole in the ground.

Let's talk about the specific plants you'll want. Hornwort is my go-to oxygenator — it floats freely in the water and absorbs massive amounts of nutrients. Water lilies are essential too. Their broad leaves shade up to 70% of the water surface, which starves out algae that need sunlight to bloom. Around the edges, use marginal plants like cattails, aquatic iris, and pickerel weed. These grow in shallow water and their roots act as natural filters. I always tell clients to include at least three different species in the regeneration zone. This diversity ensures that if one plant struggles, another will pick up the slack. Duckweed gets a bad reputation, but it's actually a fantastic nutrient sponge. Just keep it contained — it spreads like crazy. If you want a low-maintenance pool, focus on hardy native species. They're already adapted to your climate and won't need fertilizer or special care.

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Liner vs. Clay vs. Concrete: Which One Should You Pick?

You can make your natural swimming pool look like a tropical oasis, a Japanese garden, or a native prairie. The plants you choose set the entire mood. I love using sedges and rushes for a soft, naturalistic look, and adding pops of color with water primrose or aquatic canna.

Here's a planting scheme I've used successfully. Outside the pool, plant azaleas and Japanese maples for structure and color. In the shallow regeneration zone, use sweetflag and golden sword for vertical interest. In the deeper water, drop in a few water lilies and lotuses. Lotus flowers are stunning, but they're heavy feeders and can take over if you're not careful. I recommend planting them in submerged pots to control their spread. For the floating layer, add frogbit or water lettuce — their roots dangle in the water and provide additional surface area for bacteria. The result is a pool that feels like a natural spring hidden in the woods. I designed one for a couple in Oregon who wanted a swimming hole that blended into their forested backyard. We used native ferns, sedges, and a small waterfall. They said it felt like swimming in a fairy tale. That's the magic of a thoughtful natural swimming pool design.

Natural Swimming Pool Maintenance and Seasonal Care

Daily and Weekly Maintenance: It's Easier Than You Think

Here's the truth: Natural swimming pools require less maintenance than traditional pools, but they're not zero maintenance. You still need to skim leaves off the surface and check the water level, especially during hot spells when evaporation is high.

I recommend spending about 10 minutes a week on your natural pool. Use a long-handled skimmer net to remove leaves and debris from the swimming zone. Check the pump intake to make sure nothing is blocking it. Once a month, trim back any dead or dying plant material in the regeneration zone. Leaving dead plants in the water releases nutrients back into the system, which can cause an algae bloom. You should also top off the water as needed — a garden hose works just fine. If you notice the water starting to look green, don't panic. It usually means the plants are still establishing, or you're getting too much sunlight. Adding more floating plants like water lilies can fix this quickly. In the spring, you might need to thin out the plants if they've grown too dense. Think of it like weeding a garden, except you get to swim in it afterward.

Winterizing Your Natural Pool: Let It Sleep

If you live in a cold climate, don't drain your natural swimming pool for winter. The ecosystem needs to go dormant naturally. Draining it disrupts the bacteria colony and kills your perennial plants. Instead, let the water freeze and the plants die back.

Here's my winter routine. In late fall, cut back the dead foliage on marginal plants to about 6 inches above the waterline. Remove any tropical plants that won't survive the frost. Place a de-icer or a small pond heater in the swimming zone to keep a hole open in the ice. This allows gases to escape and oxygen to enter, which keeps any fish or beneficial bacteria alive. Don't run the pump once the water temperature drops below 40°F (4°C) — ice can damage the impeller. I've used this method on my own pool for five years, and it comes back to life every spring without fail. As the ice melts and the plants regrow, the water clears up naturally within a few weeks. You don't need to do anything except sit back and wait for swimming season to start.

Cost, Size, and Location: Planning Your Natural Pool

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Liner vs. Clay vs. Concrete: Which One Should You Pick?

One of the biggest reasons people switch to natural swimming pools is cost. A conventional in-ground pool runs $50,000 to $80,000 easily. A DIY natural swimming pool can be built for $2,500 to $10,000, depending on size and materials. Even hiring a professional designer usually lands between $15,000 and $30,000 — still half the cost of a traditional pool.

Let's break down the budget. The biggest expense is excavation, which runs about $200 to $500 for a small machine rental. The liner costs $300 to $800 for an average 300-square-foot pool. The pump and plumbing add another $400 to $1,000. Plants are surprisingly cheap — $5 to $20 each, and you only need about 10 to 15 plants for a good start. The hidden cost is landscaping around the pool. If you want a beautiful stone deck, pathways, and lighting, that can add another $2,000 to $5,000. But here's the thing: you can build it in stages. Start with the pool itself, then add the surrounding features over time. I helped a client do exactly that. He built the pool one summer, added a deck the next, and a waterfall the year after. It's a project you can grow with.

Choosing the Right Spot: Sun, Soil, and Trees

Location matters more than you think. Your natural swimming pool design depends on getting the right amount of sunlight — about 6 to 8 hours per day for the plants to thrive, but enough shade to keep algae in check. If the spot gets full, harsh sun all day, you'll struggle with algae despite your best efforts.

Avoid placing your natural pool directly under large deciduous trees. The falling leaves in autumn can overload the system with organic matter. Evergreens are better neighbors because they drop less debris. Check your soil drainage too. Heavy clay soil can cause water to pool around the edges, which leads to muddy banks and erosion. If you have clay, plan to add a drainage trench or a gravel border around the pool. Also, keep the pool at least 10 feet away from your house foundation and any septic systems. You don't want water seeping into places it shouldn't. I once had a client who ignored this advice and ended up with a wet basement. Don't be that person. Spend a day walking your property, observing how water flows during a rainstorm, and picking a spot that drains naturally. Your future self will thank you every summer.

Have you ever dreamed of jumping into a cool, clear swimming hole without the red eyes and chlorine smell? You are not alone. I've been designing backyard landscapes for over a decade, and more people than ever are asking me about natural swimming pools. These aren't just fancy ponds — they're fully functional swimming spots that use plants and gravel to keep the water clean. And honestly, they're way easier to build than you think. Let's walk through everything you need to know about building natural swimming pools so you can start planning your own.

Common Misconceptions About Natural Swimming Pools

Myth #1: Natural Pools Are Just Muddy Ponds

I hear this one all the time. People imagine a green, murky mess where you can't see your feet. That couldn't be further from the truth. A well-designed natural swimming pool has water so clear you can see the bottom at 6 feet deep.

The confusion comes from mixing up a natural swimming pool with a regular garden pond. A garden pond is designed for fish and frogs — it's intentionally murky to support aquatic life. A natural swimming pool is a completely different beast. The regeneration zone isolates the plants from the swimming area, so debris and nutrients get processed before they reach your swimming zone. I've seen pools that look like a mountain spring — crystal clear, no algae, and zero chemicals. The trick is getting the plant-to-water ratio right. If you skimp on the regeneration zone, you'll end up with a green mess. But if you follow the 50-50 split, your water will stay pristine. Don't let the skeptics fool you — this system works.

Myth #2: Natural Pools Are High Maintenance

Let me set the record straight. Natural swimming pools actually require less maintenance than a traditional chlorine pool. You skip the weekly chemical testing, the pH balancing, the shocking, and the algae treatments. Instead, you spend about 10 minutes a week skimming leaves and checking the pump.

Here's a reality check. I've maintained both types of pools for clients, and the difference is night and day. A traditional pool needs you to test the water chemistry every 2-3 days, adjust chemical levels, run the filter for 8-12 hours daily, and scrub the walls weekly. That's easily 3-4 hours per week during swimming season. A natural pool? You skim the surface, trim a few dead leaves, and top off the water. That's it. The plants and bacteria do the heavy lifting 24/7. Think about it this way: your natural pool is a self-cleaning ecosystem. You're just a caretaker, not a chemist. The only real maintenance is in the spring and fall when you trim plants and prepare for winter. For the rest of the year, you can actually enjoy your pool instead of working on it.

Myth #3: Natural Pools Are Expensive to Build

Here's the truth that surprises most people. Building natural swimming pools costs a fraction of conventional pools. A standard in-ground pool runs $50,000 to $80,000. A DIY natural swimming pool can be built for $2,500 to $10,000. Even hiring a pro costs only $15,000 to $30,000.

You might wonder where the savings come from. It's simple — you're not buying expensive filters, pumps, heaters, or chemical treatment systems. The plants are your filtration system, and they're free after the initial purchase. The pump you need is much smaller than a traditional pool pump because it only circulates water, not forces it through a filter. I built my first natural pool for under $5,000 — a 300-square-foot swimming area with a generous regeneration zone. The liner cost $600, the pump $400, the plants $200, and excavation was $1,500. Compare that to a traditional pool where the filter system alone can cost $2,000 to $5,000. The savings are real, and they keep coming. You'll never buy chlorine, shock, or algaecide again. Over 10 years, that's thousands of dollars saved.

Water Quality and Health in Natural Pools

How to Test Your Natural Pool Water

You don't need a chemistry lab, but you should monitor a few key parameters. pH, temperature, and oxygen levels are the main things to watch. A simple test kit from a pond supply store costs about $20 and lasts a whole season.

I recommend testing your natural swimming pool water once a week for the first month after you fill it. After that, once a month is usually enough. The ideal pH range is 6.5 to 8.0 — slightly basic is fine. If your pH drops below 6.0, the water can become acidic and irritate your skin. If it goes above 8.5, the plants might struggle to absorb nutrients. Temperature matters too. Natural pools stay cooler than traditional pools because they're shallower and have plant shade. That's actually a benefit in hot climates — you get a refreshing dip without the shock of ice-cold water. Oxygen levels should stay above 5 mg/L for healthy bacteria and plants. If you see fish gasping at the surface, it's a sign of low oxygen. But in a well-designed natural pool, you won't have fish, so that's not a concern. The key is consistency. Once your ecosystem stabilizes, you'll rarely need to check anything.

Are Natural Pools Safe for Kids and Pets?

Absolutely. Natural swimming pools are safer than traditional pools in many ways. No chemicals mean no risk of chemical burns, eye irritation, or accidental ingestion of harsh substances. The water is as clean as a natural spring.

You might be worried about bacteria or algae. Here's the thing: natural pools are not stagnant water. The constant circulation through the regeneration zone keeps the water oxygenated and moving. Beneficial bacteria outcompete harmful bacteria, and the plants consume nutrients that would otherwise feed algae. I've had clients with toddlers and dogs who swim in their natural pools every day without any issues. The shallow water is safer too — most natural pools are only 4 to 5 feet deep, so there's no risk of diving accidents. One safety tip: install a gentle slope entry instead of stairs or ladders. This makes it easy for kids and pets to get in and out. Also, consider adding a shallow kiddie zone that's only 1-2 feet deep. It's a game-changer for families. You can relax while the kids splash around without worrying about chemicals or deep water.

Wildlife and Biodiversity in Natural Pools

Attracting the Good Guys: Frogs, Dragonflies, and Birds

One of the best surprises of owning a natural swimming pool is the wildlife it attracts. Frogs, dragonflies, and birds will find your pool within weeks. These creatures are not pests — they're your natural pest control team.

Let me explain why this is a good thing. Dragonflies are voracious mosquito eaters — a single dragonfly can eat hundreds of mosquitoes per day. Frogs eat insects and keep the ecosystem balanced. Birds visit to drink and bathe, adding to the peaceful atmosphere. I've seen clients' natural pools become a hub of biodiversity within a single season. One client in Texas had a pair of green tree frogs that lived in the marginal plants all summer. They became a family attraction. The kids named them "Splash" and "Ripple." The key is to create habitat — plant native grasses and shrubs around the pool, add a few flat rocks for sunbathing, and leave some shallow water areas for small critters. You're not just building a pool; you're creating a mini-ecosystem that supports local wildlife. And because there are no chemicals, the animals are safe to drink and bathe in the water.

Managing Unwanted Visitors: Mosquitoes and Algae

Let's address the elephant in the room. Natural swimming pools can attract mosquitoes if you don't manage them correctly. But the solution is simple: keep the water moving. Mosquitoes only lay eggs in stagnant water, so your pump running 24/7 prevents them from breeding.

I've found that mosquito dunks (Bti bacteria) are a safe, natural solution if you notice a problem. They kill mosquito larvae without harming other wildlife. But honestly, I rarely need them. The frogs and dragonflies that your pool attracts do a great job of keeping the mosquito population in check. Algae is another concern, but it's manageable. If you see green water, it usually means your plants aren't established yet, or you're getting too much sunlight. Add more floating plants like water lilies or duckweed — they'll shade the water and starve out the algae. You can also use a UV clarifier if you want a quick fix. These devices kill algae spores without chemicals. But I've found that patience works best. Give your ecosystem 4-6 weeks to stabilize, and the algae will naturally disappear. The key is balance — too many nutrients, too much light, or too few plants will tip the scales. Once you dial it in, the pool maintains itself.

Advanced Building Tips for Natural Pools

DIY vs. Professional Build: Which One Is Right for You?

I've seen people build amazing natural swimming pools on their own, and I've seen professional builds that are works of art. The right choice depends on your budget, your skills, and how much time you have. DIY is absolutely doable if you're handy with a shovel and can follow a plan.

Here's how I help clients decide. If you have a weekend and a strong back, go DIY. You can dig a pool, install a liner, and set up the pump in two days. The plants take another day to arrange. Total cost: $2,500 to $5,000. If you want a more complex design — like a waterfall, a stream, or an irregular shape — consider hiring a professional. They can handle the excavation, plumbing, and landscaping. Expect to pay $15,000 to $30,000 for a turnkey project. One thing I always recommend: if you're going DIY, start small. Build a 150-square-foot pool first. Learn the process. Then you can expand later. I've seen too many people bite off more than they can dig and end up with a half-finished hole in their backyard. Start small, learn the system, and then scale up. You'll save money and frustration.

Choosing the Right Pump and Plumbing for Your System

Your pump is the heart of the natural swimming pool. It moves water from the swimming zone to the regeneration zone and back. You don't need a massive pump — a small, energy-efficient model works best. The goal is gentle circulation, not high-pressure filtration.

I recommend a submersible pump rated for 1,000 to 2,000 gallons per hour for a typical 300-square-foot pool. That's enough to cycle the entire volume of water through the regeneration zone every 2-3 hours. Solar-powered pumps are a great option if you're off-grid or want to reduce your energy use. They cost more upfront ($500 to $1,200) but save money on electricity over time. Plumbing is straightforward — use 1.5-inch to 2-inch PVC pipes to connect the pump to the regeneration zone. Place the pump in the deepest part of the swimming zone, and direct the outflow into the top of the regeneration zone. The water then flows through the gravel and plants, and returns to the swimming zone via a spillway or a simple overflow. I've used this setup on dozens of pools, and it works flawlessly. The key is to keep the pump accessible for cleaning. Build a small sump or a pump vault that you can lift out easily. You'll need to clean the pump intake once a month to remove debris.

Seasonal Adjustments and Troubleshooting

What to Do When Your Water Turns Green

Don't panic. Green water in a natural swimming pool is almost always a temporary problem. It usually means your plants are still establishing, or you're getting too much sunlight. The fix is simple: add more floating plants.

I've seen this happen every spring, even in well-established pools. The water clears up naturally as the plants start growing. If you want to speed up the process, add a few bunches of hornwort or water lettuce. These plants are nutrient hogs and will clear the water in a week or two. You can also use a barley straw bundle — it releases natural compounds that inhibit algae growth. Just drop it in the water and let it work. One thing I warn against: don't dump in chemicals to kill the algae. It will kill your plants too, and you'll have to start over. Be patient. Your ecosystem needs time to balance. If the green water persists for more than a month, check your pump flow. A clogged pump can reduce circulation and cause stagnation. Also, make sure you're not overfeeding the system — if you have fish, reduce feeding. Fish waste adds nutrients that fuel algae growth.

Extending Your Swimming Season Naturally

You can extend your swimming season by a few weeks on each end with a few simple tricks. Natural swimming pools warm up faster in the spring because they're shallower and have less thermal mass. But you can make them even more usable.

I recommend using a solar cover (a clear bubble wrap blanket) on cool nights. It traps heat and prevents evaporation, keeping the water 5-10°F warmer. You can also build a windbreak — a fence or hedge on the north side of the pool blocks cold winds and keeps the water warmer. In the fall, add a few black rocks or stones to the bottom of the pool. They absorb heat during the day and release it at night, keeping the water temperature stable. I've seen clients swim comfortably into October using these methods, even in cooler climates like Minnesota. The key is to think about microclimate. A sunny, south-facing spot with a windbreak can be 10-15°F warmer than a shaded, exposed spot. If you're planning a new pool, choose your location with this in mind. You can also add a simple solar heater — a coil of black hose on a sunny roof — to warm the water on demand. It's a low-tech solution that works surprisingly well.

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FAQs

Q: How much does it actually cost to build a natural swimming pool, and is it really cheaper than a traditional one?

A: I get this question every single time I talk to someone about natural pools, and the short answer is yes — they are significantly cheaper. A conventional in-ground pool will set you back $50,000 to $80,000, sometimes more depending on your location and features. A DIY natural swimming pool, on the other hand, can cost as little as $2,500 to $10,000. Even if you hire a professional designer, you are looking at $15,000 to $30,000, which is still roughly half the cost of a traditional pool. The biggest savings come from ditching expensive chemical systems and complicated filtration. Instead of paying for chlorine, pH adjusters, and algaecides year after year, you invest in plants and gravel that do the work for free. The one hidden cost people often overlook is landscaping around the pool. If you want a stone deck, pathways, or a waterfall, that can add another $2,000 to $5,000. But here is the thing — you can build it in stages. I have worked with clients who started with just the pool one summer, added a wooden deck the next, and installed a waterfall the year after. It is a project that grows with your budget and your vision.

Q: Can I really swim in a natural swimming pool without chemicals, and will the water stay clean?

A: Absolutely, and I have the client photos to prove it. The secret is in the two-zone system. About 50 to 60 percent of your pool is the regeneration zone, filled with gravel and aquatic plants. The other 40 to 50 percent is your swimming area. A small pump continuously circulates water from the swimming side into the plant zone, where billions of beneficial bacteria living on the gravel surfaces break down organic waste like skin cells, sunscreen, and fallen leaves. The plant roots then absorb the nutrients that result from that breakdown. By the time the water flows back into the swimming zone, it is crystal clear and perfectly safe. I have seen systems that have been running for over five years with zero chemical additives. The water clarity rivals any chlorine pool I have ever tested. One thing I always tell new pool owners is to be patient during the first few weeks. The ecosystem takes about four to six weeks to fully establish. You might see a green tint initially as the plants get settled, but once they start growing, the water clears up naturally. After that, it is smooth swimming all season long.

Q: What common mistakes do people make when building a natural swimming pool?

A: Having helped dozens of homeowners build their first natural swimming pool, I can tell you the biggest mistake is rushing the site selection. People often pick the spot that looks prettiest in their yard without considering sunlight and tree coverage. If your pool gets full, harsh sun for more than eight hours a day, you will fight algae constantly. On the flip side, too much shade from large deciduous trees means falling leaves will overload your filtration system every autumn. Another mistake I see all the time is skimping on the underlayment when using a liner. I once skipped it on a client's pool to save time, and a sharp pebble poked a hole within a month. Trust me, take the extra hour to lay down a protective layer of sand or old carpet. People also underestimate the importance of the 1:3 slope ratio for unlined pools. If you make the walls too steep, soil erosion becomes a nightmare. Finally, do not plant invasive species like duckweed without containment. It seems harmless, but it can take over your regeneration zone in weeks. Stick to native, hardy plants and keep everything in balance from day one.

Q: Which plants should I choose for my natural swimming pool, and how many do I actually need?

A: The plant selection is where your natural swimming pool design really comes to life, and I have a few tried-and-true favorites. You need three types of plants: oxygenators, floating plants, and marginal plants. For oxygenators, Hornwort is my absolute go-to. It floats freely and absorbs massive amounts of nutrients, keeping the water clear. Water lilies are non-negotiable — their broad leaves shade up to 70 percent of the water surface, starving out algae that need sunlight to grow. Around the edges, use marginal plants like cattails, aquatic iris, and pickerel weed. Their roots act as natural filters. I recommend at least three different species in the regeneration zone for diversity. If one plant struggles, another will pick up the slack. As for quantity, you only need about 10 to 15 plants for a standard 300-square-foot pool. That might sound like too few, but remember, these plants will spread and multiply over the season. A common mistake is overplanting. Too many plants can actually create dead zones where water stops circulating. Start with the minimum, see how your pool responds, and add more next season if needed. And please, use submerged pots for aggressive growers like lotus. They are stunning, but they can take over your entire regeneration zone if left unchecked.

Q: How do I take care of a natural swimming pool in winter, and do I need to drain it?

A: Do not drain your natural swimming pool for winter. That is the number one rule, and ignoring it can destroy your ecosystem. The bacteria colony and perennial plants need to go dormant naturally. Draining the water kills them off, and you will have to start from scratch in spring. Instead, follow my winter routine. In late fall, cut back dead foliage on marginal plants to about 6 inches above the waterline. Remove any tropical plants that will not survive the frost. Then, place a de-icer or a small pond heater in the swimming zone to keep a hole open in the ice. This hole allows gases to escape and oxygen to enter, which keeps your beneficial bacteria alive through the cold months. Do not run your pump once the water temperature drops below 40°F (4°C), because ice can damage the impeller. I have used this exact method on my own pool for five winters now, and every spring, the water clears up naturally within a few weeks as the ice melts and plants regrow. You do not need to add anything or do any special treatment. Just sit back, wait for the warm weather, and enjoy watching your pool come back to life. One caution: if you have fish in your pool, they will need extra care during winter, but for a standard swimming pool without fish, this routine works perfectly.