Gardening – Potted solution for tricky site

A garden in Whangaparāoa is positive proof that the most difficult site can be turned into a productive garden.

Nathan Shiu’s small, steep clay-based site would be enough to put many gardeners off. But while Nathan was growing up in Fiji, his grandmother (who lived to 103 years old) taught him the value of soil structure and only ate what she grew.

Now a retired teacher of chemistry, biology and mathematics, Nathan combined his grandmother’s teachings with his knowledge of those three subjects to create healthy soil for individual plants.

The soil in his garden is mainly clay, so its structure is definitely not ideal for healthy plant growth. But neither was a normal potting mix – “Where do you find a natural soil structure that is like potting mix?” Nathan asks.

Instead, with his understanding of the soil minerals that each plant required, he made up his own mixes and filled pots with specific ingredients for specific plants. The mix includes potting mix and Nathan’s own compost but he says clay particles are “the magic ingredient” that he added in various percentages – 30-50 percent for tomatoes and 10-15 percent for carrots. He says clay particles are negatively charged and attract and hold positively charged particles such as calcium, potassium and magnesium. Clay, importantly, also helps to retain water.

Nathan’s section does not have any in-ground plantings, but instead is covered with a multitude of pots that contain Asian tropical vegetables such as eggplant, okra, bitter melons, yard long beans, Malabar spinach, roselle and amaranthus, all of which grow among tomatoes, beans, cucumbers, peppers, herbs and flowers.

The various plastic pots and containers can be easily moved around as the seasons change, which is helpful because the land is shaded by nearby trees.

As there is an overabundance of homegrown vegetables for Nathan and his family, he gives the surplus produce away to Love Soup and other charities, as well as his many friends.