Windmill palm is one of the most cold hardy palms available. It is beautifully compact and grows to heights of 20-40 ft (6.1-12.2 m). Windmill palm has a rather slender single stem that is 8-10 in (20-25 cm) in diameter and is typically a bit narrower at the base than at the top. Trunks are usually covered with a loose mat of coarse gray or brown fiber. In older individuals the fiber sloughs away to reveal a smooth ringed surface. Chusan palm, as it is also commonly called, has light to dark green palmate leaves that are lighter, almost silvery (glaucous), on the underside. They are held on thin 3 ft (0.9 m) flattened stems that are finely toothed along both edges. Leaves are circular, about 3 ft (0.9 m) in diameter and segmented about halfway. They are flat with leaf segment tips held stiffly, but occasionally you will see individuals with droopy tips. Leaves are arranged into a symmetrical crown that is about 8-10 ft (2.5-3 m) wide. Specimens grown in full sun and/or under poor conditions may have much smaller, more compact crowns.
Hardy zone 7-11
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Sowing instructions
Soak the seeds for 24-48 hours Change the water several times during this period. Keep the soaking seeds in a warm place. Clean the seeds. Get rid of any flesh or hairs (if possible) adhering to them. Fungus is a big problem with some germinating palm seeds. Although you can treat them with fungicides, these are not always particularly efficient. Fungus loves the flesh of seeds, so clean it off!
Place the seeds in a sterile medium which is only barely moist. The biggest problems I had when I started growing palms were due to the fact that the germinating medium was too wet. This grew lots of mold, but not many palms. These days, I use a 1 pint measure - about 550ml - of vermiculite moistened with two tablespoons of water. The resulting vermiculite should feel quite dry to the touch. Nevertheless, don't be tempted to add more water. I have germinated seeds in as little at 10ml of water to 1 pint of vermiculite.
Seal the seeds in an airtight container - such as a plastic sandwich box or a plastic bag.
Place it in a warm-to-hot position, Temperatures of 90 degrees F are ideal.