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Madeira vine, Anredera cordifolia, is sold as a leaf vegetable in parts of Asia and it is a genuinely good hot-season green. It is also one of the most serious environmental weeds anywhere with mild winters. In Australia it is a Weed of National Significance, it is listed and regulated in New Zealand, South Africa and across the Pacific, and it is banned or restricted in a number of countries and states outright. Check your own local list before you plant it. If it is prohibited where you live, that is the end of the matter, and no growing method makes it legal.
What makes it so dangerous is the way it reproduces. The stems produce warty aerial tubers at the leaf joints, from pea-sized up to the size of a walnut, and they fall off at the slightest knock. Every one of them grows. A vine over a fence sheds hundreds in a season, they roll, they wash down gutters and drains, they ride in green waste and in the soil of a shared pot, and they stay alive underground for years. It also makes fat underground tubers, and any fragment left in the ground regrows. A single plant genuinely can seed a whole neighborhood, and once it is into a tree canopy or a bank of native scrub the weight of it pulls the canopy down.
So there is exactly one responsible way to grow this plant in the home garden: a container, standing on a hard surface, with the tubers collected and destroyed. If you cannot commit to that for as long as the plant lives, grow something else. Malabar spinach, sweet potato leaves or New Zealand spinach give you a similar heat-season green with none of the risk.
Nothing here is legal advice, and the rules differ between countries, states and councils. Confirm your own position with your agriculture or biosecurity department before you plant, and never pass cuttings or tubers to another gardener.
Build the containment first, then plant
Set the whole thing up before you have a plant to look after. You want a pot of at least five gallons (20 L), sitting in a solid saucer or shallow tray wider than the pot, on concrete, paving or decking. Never on gravel, bark chip or lawn, because a dropped tuber disappears into any of those and roots without you ever seeing it. The tray is not for watering; it is there to catch tubers, so keep it clear enough that you can see what has landed in it.
Cover the surface of the pot itself with a disc of landscape fabric slit to fit round the stem, or an inch (2.5 cm) of coarse grit. That stops a tuber that lands on the pot from quietly rooting into your own potting mix and giving you three plants where you wanted one. Use a fresh soilless potting mix rather than garden soil, and use fresh mix each time, because it is far easier to be certain what is in a bag than in a heap.
Give the pot a permanent position and think about what is above and beside it. Do not stand it under a tree, next to a compost pile, over a storm drain, or where the roof runoff sheets across the paving in heavy rain. Water carries the small tubers surprisingly far. A wall or fence you can hang netting on, with clear paving in front of it, is the ideal spot.
| Element | What to use | Why it matters |
|---|---|---|
| Container | 5 gallons (20 L) or larger, solid sided | Fabric pots and drainage holes over soil let roots and tubers escape |
| Standing surface | Concrete, paving or decking | Any dropped tuber stays visible and can be swept up |
| Catch tray | Rigid saucer wider than the pot | Collects tubers before they reach the ground |
| Pot surface | Landscape fabric disc or coarse grit | Stops fallen tubers rooting into your own mix |
| Potting medium | Fresh soilless mix, slightly acidic to neutral | Bagged mix carries no stray tuber fragments |
| Position | Full sun, away from drains, trees and compost | Removes every route by which a tuber travels |
Planting the tuber or cutting
Madeira vine is almost never grown from seed. You start it either from one of the aerial tubers or from a stem cutting, and both root with embarrassing ease. Plant only one per pot; the vine fills a five-gallon (20 L) container on its own within a single warm season, and two crowded plants simply give you thinner stems and more work.
Plant when the weather is settled and warm, after the last frost, once nights are staying above 55F (13C). It sulks in cool soil and does nothing until the ground is above about 65F (18C), then it climbs a foot (30 cm) a week. In a cool-summer climate, start it under cover in a small pot in late winter and move it out when the danger of frost has passed, so you are not waiting until midsummer for the first cut.
- Fill and firm the pot Fill the container to within an inch (2.5 cm) of the rim with fresh potting mix, water it thoroughly and let it drain overnight. Mix in a balanced slow-release fertilizer at the rate on the bag; this is a leafy crop that will be cut repeatedly.
- Set the tuber shallowly Bury a single aerial tuber one inch (2.5 cm) deep in the center, or push a six-inch (15 cm) stem cutting in so that two leaf joints are below the surface. Both will shoot within two to three weeks in warm conditions.
- Add the surface cover Once the shoot is up and standing, lay the fabric disc or grit over the mix, fitted close around the stem. Do this early, while there is only one stem to work around, rather than after the vine has made a tangle.
- Put the support in place now Fix netting, a trellis or strings before the plant needs them. Madeira vine twines fast and untangling a shoot that has already wrapped itself around a downpipe usually snaps stems and scatters tubers.
- Water in and shade for a week Water until it runs from the base, then keep the mix evenly moist. A new tuber in blazing sun can scorch its first thin leaves, so give it light shade for the first week if the weather is over 90F (32C).
- Sweep the surface before you walk away Every time you plant, prune or repot, sweep the paving and check the tray. Get in the habit on day one and it becomes automatic later, when there really are tubers to find.
Record what you planted and where
Write down the date you planted, whether you used a tuber or a cutting, the pot size and the exact position. Note the date the first shoot broke the surface and the date it reached the top of its support. Those two numbers together tell you how much of your season this plant actually needs, and whether starting it earlier under cover is worth the trouble in your climate.
Keep a second, more important record: a note of every place a plant of this species has ever stood in your garden, with dates. Underground tubers survive for years, and if you ever move the pot or give up growing it you will want to know precisely which square yard of paving to keep watching for stray shoots. That list is the difference between a controlled crop and a slow escape.