Macadamia Varieties in the New Zealand home garden
The macadamia nut tree had been a novelty in warmer parts of New Zealand for many years. But the 'kiwifruit boom' of the mid seventies saw a sudden surge of interest in 'new crops'. Everyone wanted to find  a 'new crop' that would mimic the financial success that came from the kiwifruit 'goldrush'.
As a result, macadamias were looked on as a potentially lucrative crop for commercial orcharding. Appearance counted for everything, so the characteristics of a useful commercial cultivar centred on low sugar levels in the nuts so that the kernels didn't caramelise and turn dirty brown when they were roasted. Experience soon showed that the green vegetable bug marked and discolored the surface of kernels quite badly, making them unattractive looking, with thin shelled varieties worst affected. Commercial varieties therefore have thicker shells that resist green vegetable bug damage, and low sugar levels for optimum whiteness when roasted.
The home gardener usually eats the nuts dryed, not roasted. Sweet nuts are particularly nice. While commercial growers use machery to crack the nuts, home gardeners use held held devices. A thinner shell is useful for home nut cracking.
A few very thin shelled trees have turned up over the years amongst seedling trees, but while mentioned as a curiosity, they are rarely propogated because the orientation is to thick shelled commercial varieties. Commercial varieties are selected for early cropping and heaving crops - characteristics sought by the avergage home gardener. Most varieties on sale are in fact commercial varieties, and they are generally productive and reliable.
Sweet, thin shelled, productive varieties are almost non existant. But sweet varieties, chiefly of the species Macadamia tetraphylla and its hybrids, are available from time to time. Different macadamia varieties are hard to find in general, with garden centres usually only carrying the variety 'Beaumont'. Many different cultivars were introduced from Australia, South Africa, and United States (California and Hawaii), and some local selections were also made. The varieties listed here are only a few of the more important commercial cultivars and home garden selections. Many are now difficult or impossible for the home gardener to obtain.
Pros and cons of growing macadamias in the home garden Beaumont
A hybrid commercial vareity widely planted in New Zealand, high in oil, but not sweet. It is one of the quickest vareities to come into bearing once planted in the garden, usually carrying a useful crop by the fourth year, and improving from then on. It crops prodigously when well pollinated. The impressive grape-like clusters of nuts are sometimes so heavy they break the branchlet they are attached to. In commercial orchards, it has reached 18kg of nuts per tree by 8 years old! Nelmac 2 is believed to be a particularly effective pollinizer. On the downside, the nuts don't drop from the tree when ripe, and the leaves are a bit prickly when you are reaching into the interior of the tree during harvest. Beaumonts' shell is easier than most commercial varieties to open.
This tree has attractive white flowers, comes into bearing very quickly, is very productive, and has a relatively thin shell.
A M. tetraphylla selection propogated by Cheddar Valley Nurseries exclusively for the home garden for its sweet nuts and productivity.
A small tree, slightly prone to yellowing of the foliage when stressed, that bears very heavy crops of bunches of small sweet nuts. It is probably fully self fertile, as the original tree was an isolated seedling with no other macadamis near by. The nuts fall from the tree toward the end of the season, around early August.
Low sugar commercial variety, useful for the home gardener because the nuts drop when ripe, it pollinates Beaumont, and is a fairly small, compact tree. On the downside, it is quite prickly, and the nuts are prone to green vegetable bug damage.
Nelmac I
A high oil, bland tasting commercial variety. The tree is slow to come into bearing, the shell is particularly thick, it crops fairly lightly, and doesn't overlap it's flowering with other vareities as completely as some others. On the plus side, it is a very heavy flowering tree, the nuts fall when ripe, and the tree is open with naturally strong wide angles branches..
Nelmac II
This tree is fairly compact, but has washed out whitish yellow ('chlorotic') new growth. As long as the tree is well fed, it is nothing to worry about, it is just a peculiarity of this variety. It is a bit slow to 'get going' when first planted. The nuts are particularly large, pleasant, and sweet. They drop over quite a long period - last nuts falling in november, when all the rest are finished about the end of september - and are one of the first to ripen at the beginning of the season. Altho' the nuts don't hang in large clusters, its overall productivity is high, with commercial orchards getting 22kgs of nuts per ten year old tree. It is said to be a pollinator for Beaumont. Apart from needing a bit of extra care in feeding and mulching terms, the downside is that the nut is thick shelled and large. With an efficient hand held cracker, this disadvantage actually becomes an advantage, as you get more nut meat for each nut opened.
Originally released by Gordon Titirangi Macadamia nursery as a pollinator for Beaumont, a small nut is with a high oil content.
Also a Gordon Titirangi Macadamia nursery selection, a thin shelled selection, with moderate cropping. As with all thin shells, green vegetable bugs can cause quite a bit of brown spotting on the kernel due to their piercing sucking mouth parts penetrating the still developing immature nut.
Own Choice
A high oil low sugar commercial variety. It is said to be a good pollinator for Beaumont, crops moderately well, and may be  self fertile. On the downside, the nuts have to be picked when ripe.
A M. tetraphylla variety, the tree is productive, and the small nut has a particularly good flavor. It is said to be a good pollinator for Beaumont.
Nutty Glen
An Australian hybrid selection. The nut is large and of good quality. It is popular in Australia as a rootstock.
A variety selected by Hans Lens in the mid 80's for its sweetness and thin shell.
A rather spreading tree. On the plus side it is high yeilding (commercially, 17 kgs off a 9 year old tree has been recorded), and the nuts drop to the ground.But the nut is thick shelled, and with not much flavor.
Note: this article (and this article only only)  'Macadamia Vareties in the New Zealand home garden' may be freely distributed for private or commercial purposes PROVIDED that the author is clearly attributed in the format customary in countries signatory to the Berne Convention (i.e. the article title in larger font immediately above the text, and the author in smaller, but prominently set font and style immediately under the title) AND PROVIDED the publishers internet universal resource location address is given, i.e. 'www.naturalhub.com'. UHIS asserts its moral right to be clearly  identified as author. Nevertheless the work is © Copyright UHIS, regardless that it is permitted to freely distribute it.

Visit our website at www.naturalhub.com
 L2 Lucida Sans