Palms in Austria

By Robert Lackner

The area where I live has generally Austria's most favoured climate. It is situated about 30 miles east of Vienna and the climate is influenced by continental impacts, i.e. on one hand the summers are normally hot (average daytime temp.: +28°C (82°F)), spring and autumn quite mild, but on the other hand winters can bring heavy frost. Usually the absolute lows in winter are -12°C (+10°F) to -15°C (+5°F) once or twice a winter, making us a zone 7b. Some winters are much milder, others can be worse. The last two winters were pretty severe and brought endless frost periods with severe temperatures.

During the previous winter we even reached the impressive low of -22°C (-8°F) !, 3 out of 13 Trachycarpus succumbed, but the other 10 survived in fairly good condition. Most of them defoliated, but refoliated quickly in spring, my largest Trachy (10 feet) however avoided complete defoliation and lost only a couple of its fans. This is likely because of its very sheltered location.

I should mention that all Trachycarpus were unprotected apart from some straw placed around the base. Only my largest Trachy is covered with an unheated plastic frame erected over it. Also a Trachycarpus wagnerianus (5 feet) defoliated completely but has until now produced 10 new lovely fans. Also in my garden I house a Washingtonia filifera (10 feet), a Washingtonia robusta (5 feet) and a Jubea chilensis (3-4 feet). These plants are well protected during severe winters like this one. (See palm protection, below).

The negative surprise this winter had in store for me were two 5 feet large Rhapidophyllum hystrix (Needle palm) which were completely killed. True, it was their first winter outside and they were unprotected, but I expected they could withstand -22°C.

I have some new palm species at home which you should probably keep an eye on, namely:

Trachycarpus takil:

Allegedly hardier than T.fortunei. But attention T.takil is sold generally in the US as T.wagnerianus which it definitely isn't. Only young plants of T.takil are momentarily available. It resembles T.fortunei, whereas T.wagnerianus has considerably stiffer and smaller fans.

Chamaerops humilis var. 'Cerifera':

Quite exciting palms. It looks likethe well know Chamaerops palm only that its fans are intensively blue (like Brahea armata). It is hardier than the plain green form of Chamaerops humilis and should tolerate equally low temperatures like Trachycarpus fortunei. It can cope very well with heavy snow and has to be protected probably only during our worst of winters

Palm Protection

I do protect Washingtonia and other less hardy palms with electric warming cables. They are very effective as they carry the warmth exactly to those points where it is needed, namely close to the plant itself. The warming cables were set to activate at -5 to -7°C (+20°F) and turn off at 0 to +5°C (32 to 42°F).

As the cables warm up exceedingly fast they are only active for 1 or 2 minutes at a time. So it was possible to protect a 4 feet Washingtonia during this exceptionally bad winter with costs of only 60 cents. The plants were unwrapped in February and left to struggle with the elements from then on.

Quite astounding: They withstood two -5°C (24°F) nights and another night where the temperature dropped to -7°C (20°F) completely unharmed, also a 5 feet Washingtonia robusta, which is allegedly hardy to only -5°C(24°F) when mature. I think the main point was that the temperature did rise well above freezing during the day.

The Jubeas were protected in the same way, only that they are hardier and therefore the cables were set to activate at -7° to -10°C, which caused costs of only 20 cents.

The only drawback is that warming cables are usually rather expensive, but it is certainly not as expensive as losing a large palm. Furthermore it gives me the possibilty to grow even more tender palms outside. I'd rather purchase a faster growing (thus cheaper) and more beautiful palm and invest in a set of cables than struggle around with these relatively slow growing ultra-hardies (Rhapidophyllum, Sabal), which will never achieve the real charm of a palm.

Luckily there are other hardy and fast growing palms, which do reach quite good heights, like Trachcarpus takil, wagnerianus, fortunei, Chamaerops humils var 'Cerifera'.

A last remark:

In my opinion Trachycarpus takil is not only hardier (it is said to withstand -5°F regularily, compared with T.fortunei's 0°F) but also more picturesque, because its trunk sheds naturally when it becomes older and it also keeps a Washingtonia-like petticoat. Furthermore the fans are also somewhat more appealing, but you have to decide on that yourself. T.wagnerianus is also more beautiful than plain T.fortunei, at least equally hardy and considerably more windresistant, because of its very hard and conpact fans.