Ptychosperma microcarpum

[stygiana]

I recently read on another website that Geoff Stein mentioned it as being cultivated in coastal California. Is it a succesfull species there? Anyone tried it in Southern Australia, NZ?

[Tropicgardener]

In Australia it is fairly commonly grown from northern NSW northwards............I always thought it would have similar hardiness to P. macarthurii.

[stygiana]

Thank you Andrew,

More than hardiness, it is its needs of heat that I am not sure about. It seems that it is one of the few Ptychosperma which comes from high altitude.

So I wondered if it had been tried in places where high altitude palms use to succeed (coastal California, NZ, etc).

As I explained in another post, P. macarthurii is quite hardy in some way, as it survives in SoCal and grows in coastal Andalucia (mainland Spain), thus quite far away from the tropics.

The geographical limit in SoCal and mainland Spain for P. macarthurii seems to be more or less the same as for Roystonea regia and Wodyetia bifurcata.

But P. marcarthurii seems to be more demanding in terms of heat, as it only grows up to 400 m (1,300 ft) of altitude here on the leeward side of the island (which is the upper limit for Cocos nucifera, Adonidia merrillii, Roystonea oleracea, Pritchardia pacifica, Theobroma cacao, Artocarpus altilis, Morinda citrifolia (noni), etc, all species which simply cannot grow in SoCal or Andalucia (except the few famous Cocos, which are more than borderline...). It is even limited only to the coast on the windward side.

While the upper limit for Roystonea regia and Wodyetia is much higher here, at 700 m (2,300 ft) of altitude... So it's not just a question of cold, but also a problem of needs of heat.

I have a palm tree collection project on the windward side of the island at mid-altitude, with a climate similar to northern New Zealand. To give you another example, while Delonix regia grows up to 700 m of altitude here on the leeward side, they rarely flower higher than on the coast on the windward side and simply cannot grow above 200 m. Lack of heat is the issue. We plan to create a palm trees collection there, but constantly cooler temps will be the limiting factor (although it will also allow some plants to flourish there, like Dicksonia and Ceroxylon, while they struggle here). I wondered if Ptychosperma microcarpum would be a good candidate?

I also though that this subject could be interesting for other palm enthusiasts who live in a cool frostfree climate, like coastal California, NZ, etc.