The Grandfather of Citriculture

World-renowned citrus expert Ian Tolley talks about his life's opus ‘Commonsense Citrus’.

The Grandfather of Citriculture

For over 60 years, Ian Tolley has lived and breathed citrus.

Growing up in Renmark in SA, it’s easy to imagine him as an enthusiastic young adult, throwing away years of study (Civil Engineering & Surveying) to follow his passion for plants, because he is still exudes this enthusiasm today.

A conversation with Ian is like drinking from the font of knowledge, and his help has been pivotal to the success of The Diggers Club’s citrus range. Not just a collection of nice fruits, Ian and Clive Blazey have worked together to cultivate a list of rare, unusual and garden worthy citrus, as well as a few of their favourites.

Having run a successful citrus nursery and orchard for most of his life, there is nothing that Ian does not know about citrus. In 1965 he was awarded one of the first Australian Churchill Fellowships for citriculture, enabling him to tour overseas for 6 months learning from citrus growers around the world.

Ian developed a new propagation for citrus called ‘Micro-Budding’ and this has now become an accepted technique world-wide.

Internationally renowned, he was awarded an Order of Australia Medal in 1995 for services to the community, horticulture and of course, his beloved citrus industry.

The release of Ian’s book, Commonsense Citrus – A hands-on guide to propagation and planting this year is the culmination of his life’s work in one magnificently presented almanac.

Covering everything from citrus varieties, rootstocks, planting, tree health, propagation and growing media, it is an essential reference to the professional nursery trade, and an informative compendium for the home gardener.

Landscaping with Citrus

Ian’s own passion for the conservation of heritage citrus bud-lines has resulted in an arboretum of specialist citrus, which has been kindly made available to The Diggers Club.

Both Ian and Clive share the opinion that citrus is underutilised as a landscaping and ornamental tree in Australia.

Creating productive, beautiful gardens is possible, and citrus can create a wonderful evergreen hedge or screen that flowers and fruits throughout the year.

Suitable for both Mediterranean and sub-tropical regions, citrus are hardy, have a wonderful form and grow well in most areas of Australia.

Pruning and training can greatly modify the required space, with many lemons trained to espalier to fit small courtyards and pots.

Caring for Citrus 

As a regular on ABC talkback as well as presenting popular Masterclasses for Diggers Members in Adelaide, Dromana and Blackwood, Ian is most often asked about caring for citrus.

Misshapen fruit, thick skins, discoloured leaves and, of course, voracious pests, are hot topics, and Ian recommends staying on top of all issues before they become a real problem and detriment to the tree.

Ian lists 13 pests and 12 diseases common to citrus in Australia, recommending copper sprays for most fungal and bacterial diseases. As a preventative measure, spray before autumn or winter rains arrive.

The best way to protect trees from pests is to keep them healthy. Citrus are gross feeders and enjoy regular applications of balanced organic fertilisers. Those based on composted chicken manure are ideal. Start by improving the soil and the pH. At different pH levels, different nutrients become available. Citrus prefer a soil around 5.5-6.5. At different times of the year, nutrient availability also changes with heat and soil moisture, but a good nutrient enriched soil is the best possible start.

If pests do attack, Ian recommends avoiding toxic chemicals, relying on soapy water and a toothbrush for cushiony scale, Dipel for leaf-eating grubs and Eco-Oil for scale, leaf-miner and soft bodied pests.

Ian believes there are no silly questions, and he loves to save them up until the end of the day so that the explanation and information provided throughout the day can help gardeners problem-solve their own citrus questions through their newly acquired knowledge.

A passionate marmalade connoisseur, when we spoke Ian was excitedly waiting for the Australian Festival of Marmalade to be held in Renmark in early September. Ian believes that sour oranges (like Seville, which is the perfect landscaping citrus), also make the best marmalade, followed by Bengal citron, lemons, kumquats and calamondin.

Now in his 80’s, Ian shows no signs of slowing down, and The Diggers Club is immensely humbled to have Australia’s leading citrus expert on hand to help us preserve, maintain and improve the range of citrus available to gardeners across Australia.