Quick answer: when to net a pond for fall leaves in Illinois
In the Chicago suburbs, put pond netting on in the last week of September or the first week of October, before the maples let go, and leave it until the oaks finish in mid November. Use a fine-mesh (about 3/8 inch) black polypropylene net sized at least two feet larger than the pond on every side, tent it over a hoop or a few crossing poles so leaves roll off, and pin the edges with stakes or stones. A netted pond goes into winter with far less sludge, which means less gas under the ice and a cheaper spring cleanout.
Book a fall pond shutdown · Pond cleaning and maintenance service
Every October the same thing happens in yards from Naperville to Libertyville. The maples drop in a single windy weekend, the pond skimmer clogs by Tuesday, and a layer of wet leaves settles on the bottom where nobody can reach it. By the time the oaks finish in November, that layer is an inch of sludge that will sit under the ice all winter. Pond netting is the cheapest fix in pond keeping. A $40 net, put up on the right weekend, can save a $500 spring cleanout and a lot of stress for the fish. This guide covers the Illinois timing, what to buy for your pond size, how to put it up so it actually works over a waterfall, and the point where it makes sense to hand the whole fall job to us.
When to net a pond in the Chicago area
Leaf drop in northern Illinois runs in two waves, and the net needs to be up before the first one.
- Late September to mid October: maples, birches, cottonwoods, and most ornamentals. Silver and sugar maples usually let go in one or two windy days around the second week of October. This is the wave that fills a pond fast, because maple leaves are thin, they sink within a day or two, and they break down quickly.
- Late October to mid November: oaks, and then everything the wind brings from the neighbors. Oak leaves hang on longer and fall slowly. They are leathery and slow to rot, so they do not foul the water as fast, but they pile up on the net and need to be cleared more often.
A simple rule that works across DuPage, Cook, Kane, Lake, and Will counties: net the pond the weekend the first maple in your yard shows color, which is usually the last week of September. Leave it up until the last oak is bare or the pond is ready for its winter setup, whichever comes first. If you have no trees within fifty feet of the pond, you can wait until the first leaves show up on the water, but most suburban lots do not get that luxury.
| Date range (Chicago area) | What is falling | What to do |
|---|---|---|
| Sept 20 to Oct 5 | First color, light drop | Put the net up, trim marginal plants, empty the skimmer basket daily |
| Oct 5 to Oct 25 | Maples, birches, ornamentals (heavy) | Clear the net every 2 to 3 days, check that it is not sagging into the water |
| Oct 25 to Nov 15 | Oaks (slow, leathery) | Clear weekly, watch the waterfall for leaves wedged in the rocks |
| Nov 15 to freeze | Wind-blown leaves only | Remove the net, finish the fall shutdown, set the de-icer and aerator |
What happens if you skip the netting
Leaves that reach the bottom do three things, and none of them are visible until spring.
- Sludge. Wet leaves break down into a black muck that coats the liner, the rocks, and the gravel. The pond does not clear itself of it over winter, because the beneficial bacteria that eat organic waste go dormant below about 50 degrees. A pond that takes a full leaf load usually needs a complete drain-and-rinse in spring instead of a partial clean.
- Gas under the ice. As that muck rots it gives off hydrogen sulfide and other gases. In summer they escape at the surface. In January, with the pond sealed under ice, they build up in the water where the fish are resting. This is the single most common reason we hear about koi losses in February, and a de-icer alone does not solve it if the pond went into winter full of leaves.
- Spring algae. The nutrients released by rotting leaves feed the first algae bloom of the year. Ponds that were netted in fall come out of winter clearer, and stay clearer, than ponds that were not.
The money side is simple. A professional spring cleanout in the Chicago area runs $300 to $600 for a small pond and $500 to $1,000 for most backyard koi ponds. The heavy end of each range is the pond that spent the winter under a leaf layer. A net, a few evenings of raking it clear, and a fall shutdown keep you at the light end, and often mean a partial clean is enough.
What to buy: pond netting by pond size
Pond netting is sold by mesh size and by sheet size. Both matter.
Mesh size
- 3/8 inch or 1/2 inch mesh is the right choice for leaves. It stops maple and oak leaves and most seed pods, and it is fine enough that birds do not get tangled in it.
- 3/4 inch and larger “bird netting” is meant for herons, not leaves. Maple leaves fold and slip through it. If you already own it, you can layer it over a leaf net for heron protection, but do not rely on it alone in October.
- Fine 1/4 inch “shade” mesh works but sags badly when wet and blocks so much light that submerged plants suffer. Save it for very small ponds.
Sheet size
Measure the pond at its longest and widest points, then add at least two feet on every side. The extra is what you pin to the ground, and it is what keeps the net from being pulled into the water once it carries a load of wet leaves.
| Pond footprint | Net to buy | Support |
|---|---|---|
| Up to 8 by 10 ft (patio pond) | 14 by 14 ft, 3/8 inch mesh | Two crossing fiberglass poles or a pop-up dome net |
| 11 by 16 ft (typical koi pond) | 20 by 20 ft or 20 by 25 ft, 3/8 inch mesh | PVC or fiberglass hoops every 4 to 5 feet, or a center post with guy lines |
| 16 by 20 ft and larger | 25 by 30 ft or two overlapping sheets | A frame of 3/4 inch PVC or EMT conduit, staked at the corners |
| Pond with a stream or waterfall | Add a separate 6 by 10 ft strip for the falls | Tent it over the waterfall rocks so water still runs freely underneath |
Black polypropylene is the standard material. It is UV stabilized, nearly invisible from the patio, and lasts four or five seasons if you dry it before storing it. Avoid the thin green “garden” netting sold in the vegetable aisle. It tears at the first stake and rots in one wet fall.
Things that make the job easier
- Two dozen U-shaped landscape staples or a bag of flat stones for the edges.
- A few 8 to 10 foot fiberglass driveway markers or PVC pipe for the tent poles. Tennis balls on the tips stop them from wearing through the net.
- A leaf rake with the tines taped or a soft push broom for clearing the net without snagging it.
- A long-handled pond net for the leaves that get in anyway.
How to put pond netting up so it actually works
The mistake we see most often is a net laid flat across the water. It works for a week. Then the first heavy drop lands on it, the wet leaves weigh it down, the middle sags into the pond, and now you have a net full of rotting leaves sitting in the water instead of on it. The fix is to give the net a pitch so leaves roll to the edges.
- Trim first. Cut back marginal plants such as iris and cattail to a few inches above the water, and remove any floating plants you are not overwintering. Anything left tall will hold the net up in the wrong places and tear it.
- Empty the skimmer and clean the falls. You are about to make both harder to reach. Start with them clear.
- Build the tent. For a small pond, cross two poles at the center and tie them. For a larger pond, push hoops or poles into the ground every four to five feet along the long axis so the peak is a foot or two above the water. On very large ponds a single tall center post with four guy lines to the corners works well.
- Drape the net over the frame and pull it just taut, not tight. Netting that is pulled drum-tight tears at the stakes in the first wind.
- Pin the edges every two to three feet with staples or stones, on the ground, not on the pond rock. Leave the skimmer lid outside the net or cut a flap over it so you can still empty the basket.
- Tent the waterfall separately. Run the smaller strip from above the top rock to below the last drop, held up on two or three short poles, so the water runs underneath and the leaves stay on top. Never let the net touch the falling water. A wet net freezes to the rock in November and rips when you pull it off.
- Clear it every few days during the maple drop. Sweep from the peak toward the edges, then rake the piles away from the pond. Leaves left on the net still rot and still drip nutrients into the water.
Taking the net down and finishing the fall shutdown
Once the oaks are bare, usually the second or third week of November in the Chicago suburbs, take the net off before the first hard freeze. A net frozen into the surface ice will not come off cleanly until March, and by then it has held every late leaf on the water all winter. Rinse it, let it dry on the lawn, fold it, and store it somewhere the mice cannot reach it.
The net is the first step of a proper fall shutdown, not the whole thing. After it comes off, the pond still needs the sludge that got past the net removed, the pump and plumbing handled for winter, the de-icer and aerator placed, and feeding stopped once the water is under 50 degrees. Our Midwest fall pond maintenance guide walks through the whole list, and the Illinois winterizing guide covers keeping koi safe under the ice.
When to call us instead
Netting a small pond is a one-person Saturday job. There are a few situations where it stops being worth doing yourself.
- Large ponds and long streams. Anything over about 16 by 20 feet, or a stream longer than 15 feet, needs a frame and two people. We net ponds like this as part of the fall shutdown visit.
- Heavy tree cover. If the pond sits under mature oaks and maples, the net needs clearing every other day for six weeks. Many of our maintenance clients would rather have us handle the whole fall season on a schedule.
- The leaves already went in. If it is late October and the bottom is already covered, netting now only stops it getting worse. The pond needs a fall cleanout with a pond vacuum before it freezes, and that is the job our crews do every week in November. If you want to do it yourself, our pond vacuum review covers the tools that actually pull sludge.
- Koi you cannot afford to lose. A fall shutdown done right is what gets prized fish through a Chicago winter. Netting, cleanout, plant trimming, pump and plumbing winterization, and de-icer and aerator setup in one visit is the safest way to do it.
Our Fall Pond Shutdown and Spring Opening service covers every step above across Cook, DuPage, Kane, Lake, McHenry, and Will counties, and the spring opening is booked at the same time so the pond is opened at the right water temperature in April.
Frequently asked questions
When should I put netting on my pond in Illinois?
Put the net on in the last week of September or the first week of October, before the maples drop, and leave it up until the oaks are bare in mid November. If you have no trees near the pond, wait until you see the first leaves on the water, but most suburban yards need the net up by early October.
What size mesh is best for pond leaf netting?
A 3/8 inch to 1/2 inch mesh stops maple and oak leaves and most seed pods without tangling birds. Larger bird netting lets maple leaves through. Very fine shade mesh works on small ponds but sags when wet and blocks light to submerged plants.
How do I keep pond netting from sagging into the water?
Tent it. Cross two poles at the center on a small pond, or set hoops every four to five feet on a larger one, so the peak sits a foot or two above the water and leaves roll to the edges. Pin the edges to the ground, not to the pond rock, and clear the net every few days during the heavy maple drop.
Can I net a pond that has a waterfall?
Yes. Use a separate strip of netting over the falls, held up on short poles from above the top rock to below the last drop, so the water runs underneath and the net never touches it. A net that touches the falling water freezes to the rock in November and tears when you remove it.
What happens if leaves get into the pond over winter?
They rot into sludge on the bottom, release gases that build up under the ice where the fish are resting, and feed the first algae bloom in spring. A pond that took a full leaf load usually needs a complete drain-and-rinse cleanout in April, which sits at the high end of the $300 to $1,800 range for a professional spring cleanout in the Chicago area.
Conclusion
Pond netting is a small job with a large payoff. Get the net up before the maples drop, tent it so leaves roll off, tent the waterfall separately, clear it every few days, and take it down before the first hard freeze. The pond goes into winter cleaner, the koi are safer under the ice, and the spring cleanout is faster and cheaper. If the pond is big, the tree cover is heavy, or the leaves are already in, the fall shutdown visit handles all of it in one trip.
Fall Pond Shutdown in the Chicago Suburbs
Netting, leaf and sludge removal, plant trimming, pump and plumbing winterization, and de-icer and aerator setup in one visit, with spring opening booked at the same time. See our fall pond shutdown and spring opening service or our year-round pond cleaning and maintenance.
