About Trachycarpus Fortunei

Windmill palms (a.k.a. Chusan Palms) are native to a large region of southeastern Asia, ranging from India to China, and are found in mountainous elevations above 6,500 feet. They can face extended periods of below-freezing weather as well as heavy snow in their native habitats.

All members of the trachycarpus genus share some common characteristics, such as a tall, narrow trunk, and a compact crown featuring a dense group of palmate leaves. The old, dead leaves can form a skirt around the top of the trunk. They often grow up to 30 feet when planted in warmer temperate regions of the United States, and can grow even taller in their native habitat.

Hardiness

One notable characteristic of trachycarpus fortunei is that it prefers mild summers. In fact, it will not grow in hot, tropical areas, but it seems to grow well throughout most of the southern United States, and up the west coast as far north as Vancouver.

Windmill palms can be grown to zone 7b without significant winter protection. In a sheltered site or with winter protection, windmill palms can be grown through zone 6, although defoliation may occur during cold winters. With care, the palms will usually recover from defoliation. The sensitivity of trachycarpus fortunei to defoliation may decrease as the palm becomes older and more established.

Winter Protection

Mulch heavily. Gradually remove the mulch in spring. Site in a favorable wind-protected exposure, such as the south side of a wall or building. Windmill palms are prone to fungal and bacterial crown rot under wet winter conditions. Spraying the foliage and crowns several times during the winter with a fungicide/bactericide spray will help prevent crown rot.

Growing Tips

Windmill palms prefer moist, well-drained, organic soil. Planting in partial shade is recommended, especially in areas with hot summers.

About Sabal Minor

Sabal minor, the dwarf palmetto, is native to the United States, and is considered to be almost as hardy as the needle palm. It grows naturally in the southeastern United States, and its natural habitat extends west to Texas and Oklahoma. Sabal Minor will eventually form a clump about 5-6 feet in height. It grows from a single trunk, which typically grows mostly underground. The presence of a short above-ground trunk may indicate that the plant is actually Sabal ‘Louisiana’, which may be a Sabal minor variety or a closely-related species.

Dwarf palmetto (Sabal minor)
Larry Allain @ USDA-NRCS PLANTS Database

Hardiness

Sabal minor can be very slow to establish, and this can present some problems with hardiness. For the first few years, it grows a set of juvenile strap leaves, which can be damaged by temperatures below 0°F. Damaged juvenile leaves can be very slow to regrow. It is worth protecting through the first few years, however, because established dwarf palmettos should be hardy throughout zone 6. Like needle palms, they have some tolerance to cold, wet winters. An established underground Sabal minor trunk should be able to withstand brief temperature dips below -10°F and regrow damaged or defoliated leaves. One of the hardiest known dwarf palmetto ecotypes is ‘McCurtain County’, native to southeastern Oklahoma. It has been known to survive temperatures as low as -24°F.

Winter Protection

Mulch heavily around the base, but do not completely cover the leaves. Gradually remove the mulch in spring. Site in a favorable wind-protected exposure, such as the south side of a wall or building. Provide some winter shade if possible.

Growing Tips

Dwarf palmettos prefer full sun to light shade. In colder, marginal climates, full sun is better; in hot climates, light shade is preferred. Sabal minor may grow very slowly during a mild summer. It requires the hot, humid conditions of the southeastern United States to see significant growth in a season. Mulch plants and water regularly until well-established.

About Rhapidophyllum Hystrix

Rhapidophyllum hystrix, the needle palm, is generally considered to be the most cold-hardy palm. It is a slow-growing palm with a shrub-like form, and usually does not form a large trunk. It is indigenous to the coastal southeastern United States, from Mississippi to South Carolina.

Hardiness

Conservatively, the needle palm is hardy to zone 6. It has been known to withstand temperatures as low as -20°F, but a more realistic hardiness limit is 0°F to -10°F. It is prone to foliage damage and browning during cold winter conditions, especially when combined with wind. Cold-hardiness will increase in the needle palm as it become larger and well-established.

Winter Protection

Mulch heavily. Gradually remove the mulch in spring. Site in a favorable wind-protected exposure, such as the south side of a wall or building. Needle palms are prone to fungal and bacterial crown rot under wet winter conditions. Spraying the foliage and crowns several times during the winter with a fungicide/bactericide spray will help prevent crown rot.

Growing Tips

Needle palms prefer full sun to light shade. In colder, marginal climates, full sun is better; in hot climates, light shade is preferred. Mulch plants and water regularly until well-established.

In general, clump-forming palms, those with a shrub-like form, are hardier than arborescent, or trunked palms.

Shrub-Like Palms

• Rhapidophyllum Hystrix (Needle Palm) : Zone 6
• Sabal minor (Dwarf Palmetto) : Zone 6
• Serenoa Repens (Saw Palmetto) : Zone 7b

Arborescent Palms

• Trachycarpus Fortunei (Chinese Windmill Palm) : Zone 7
• Trachycarpus Takil (Kumaon Palm) : Zone 7
• Trachycarpus Wagnerianus (Miniature Chusan Palm) : Zone 7
• Sabal Palmetto (Cabbage Palm) : Zone 7b
• Butia Capitata (Jelly Palm) : Zone 8

The hardiness ratings listed above are estimates, and assume minimal winter protection. For some palms, hardiness may increase as they become more well-established.