My biggest hothouse has a strip of lovely rich soil to grow tropical papayas, several Thai herbs and spices, including galangal.
Russell Fransham on galangal
Greater galangal, Alpinia galanga, is called kha in Thailand and is the ginger which distinguishes Thai food from other regional cuisines. Its unmistakable sweet, pine resin pungency gives the familiar gustatory zing to tom yum soups and many other Thai favourites. Just scratch the skin of a stem or rhizome and you release a cascade of mouthwatering smells.
The dried or frozen rhizomes which are usually sold in specialty shops here are a poor substitute indeed for freshly cut kha. The young shoots are sweeter, less pungent and more tender than mature rhizomes, whose taste is intense and far more complex.
Generally the rhizome is chopped into chunks then bruised with a mallet or the back of a cleaver to release the flavour during cooking. Then once the dish is served, you place these pieces to the side of the plate as they are usually too fibrous to chew. I sometimes grate the youngest tender shoots or slice them very thinly so they are edible when cooked.
Greater galangal is a slender, glossy leafed ginger about 80cm high.
It can reach 1.5m in a hothouse. It is evergreen, unlike most other edible gingers. It needs warm conditions all year and does best in a hothouse. It also needs well-drained, friable, composty soil with steady moisture and can be harvested at any time of year.
It is never going to be a pest like the notorious kahili ginger that swarms across Northland‘s hills in some areas. They are only very remotely related to each other in much the same way that cannas and bananas are related to each other.
In late summer, galangal produces tall flower spikes comprising hundreds of tiny creamy flowers with red veins but no perfume.
Rather than digging the plant up, I just scratch away the soil and cut off enough for the recipe so the rest of the plant continues to grow undisturbed. The rhizomes are about finger-thickness and I use secateurs to remove a meal-sized piece.
There are two different strains of kha in New Zealand:
red galangal which has pink rhizomes and is more cold hardy and the white rhizome form, which is sweeter but even less hardy to cold.
For some years, one or two unscrupulous sellers on Trade Me have sold what they call galangal with a mystical-sounding blurb about its flavour and uses but what they are selling in this case is actually Hedychium coronarium, the common ornamental white-flowered butterfly ginger from the Himalayas, which tastes ghastly and is not galangal. This ornamental ginger has rather beautiful, perfumed white flowers through autumn and grows vigorously outdoors even in the South Island.
Galangal will only grow outdoors very slowly, in a very warm spot and it spends much of the year looking brown and sad.
This is mainly because our winters are wet and the soil simply gets too cold.
If you don’t have a hothouse, it will grow better in a bucket-sized dark pot so the sun warms the roots and it can be taken indoors over winter to keep the soil drier and warmer. Galangal really needs to be kept above 15°C all year round, even at night.
Even in my biggest hothouse which is unheated, the clumps of kha show a lot of browning from the colder nights through winter. But by October, a flush of new shoots emerges as the soil warms, and the clump renews itself through summer and autumn.
Almost all the ingredients used in traditional Thai food are grown in New Zealand in home gardens, but kha plants are seldom seen in nurseries. They are usually passed from one family to another down the generations.
But if a few brave and adventurous growers wanted to start growing these commercially, I’m sure there would be a very appreciative market for these fresh ingredients, especially in the largest cities.
There has been an exciting new development in Northland recently.
An enthusiastic group of tropical food growers have got together to form the Tropical Fruit Growers of New Zealand (TFGNZ) and these folk are already busy exploring many new warm climate crops that could be grown commercially in the north of New Zealand.
Trials are already well under way with bananas, coffee, pineapples and prickly pear. There will no doubt be more tropical candidates to be added to this list, including greater galangal.
Commercially grown Asian spices and herbs such as galangal, ginger and turmeric could easily be another page in the story of Northland’s horticultural economy.
I see exciting times ahead for the North with TFGNZ.
Galangal red and white cultivars.
Galangal can sometimes be found in farmers’ markets.