Grow your own worm farm

Located on Level 6 of Melbourne’s Curtin House, Mexican restaurant Mesa Verde is at the forefront of sustainability in the country, having partnered with Worm Lovers founder Richard Thomas to carry out a huge eco-project on its rooftop, using Hungry Bin worm farms as its green centrepiece. Richard chats to MiNDFOOD about Mesa Verde’s game-changing garden and how you can grow your own one at home.

How did you get to be involved in worm farms?

I’m actually an ecological artist and work on all sorts of environmental projects. I’ve headed up two sustainability projects – one around forest conservation and the other around worms and composting organic waste sustainable food gardens (that’s a mouthful isn’t it). So a big part of what I do is bring all these elements  – design and functionality – to come up with an integrated, sustainable design, which really came to fruition on that project because it required all these different elements to come together.

How did the relationship with Mexican restaurant, Mesa Verde, eventuate?

It kind of evolved very organically. The owner of the building wanted to redevelop the top of the building. I pitched the idea – they decided to put in Mr Verde, they also needed to upgrade their cool-room to supply the rooftop bar so I said, ‘why don’t we build a food garden and a worm farm integrated with the cool-room, so that we can actually provide passive cooling to the cool room?’

What’s involved in that process?

If the cool room is in the shade, it is probably five degrees cooler than if it were in the blazing sun, so you therefore use less electricity to cool it. And so that was the first pitch, and then we started talking about the food we were going to grow for the restaurant. Some of the herbs and things they use in the restaurant aren’t readily available in the market, so we decided we could grow some of those ingredients in the garden with the right system.

We also grow herbs for the bar as well   – some of the lesser-known ones used in their cocktails, like olive bush and sage. We grow all these on the rooftop.

The other part of equation is the worm farm, so I’ve been involved with Worm Lovers for 10 years. We specialise in worm farming systems of all different scales. There are different angles to that – one of those is obviously on site organic waste management. Setting these up on site means we can process quite e a large amount of waste coming out of kitchen and turn this into high-grade  food source for the garden.


How do worm farms work, exactly?

Worms are supercharged; they turn food scraps into incredible superfoods – chockablock full of nutrients and beneficial microbes that create the ideal conditions for really healthy, very robust and successful food crops. Basically, the flavours you get out of food that’s grown in worm castings is second to none – they tend to be very disease-resistant, they increase fruit cropping (you can get twice as many tomatoes from a tomato plant grown in a worm casting). The fantastic thing about it is it is pH0 neutral so you can pretty much grow any plant in it. It’s been really successful.

We don’t use any synthetic fertiliser; we don’t use any pesticides. The whole principal of biological gardens is that if the soil is healthy enough, then the plant can actually resist a lot of the pests and diseases naturally.

Could you grow a worm farm at home?

Absolutely – all of our systems are based around the Hungry Bin Worm Farm – which are available to the general public – and we ship them all over Australia. We’ve got a really good manual that comes with it – it’s probably the best worm farm you can get. It’s a new design that’s only come out the last few months, designed by a Kiwi guy – it’s on wheels so you can wheel it around. One Hungry Bin will service all the food scraps of a family of five and probably produce enough high-grade compost to fertilise a decent size vegie garden. So they are available to anyone really. There’s a bit of know-how needed – there’s a bit of training and love that needs to go into it – it is a living system after all. You do need to manage the input to get the water and nutrients and so on, but once you get it right, it’s pretty self-sustaining.

For more information on Hungry Bins and how to start your own worm farm, click here.

Citrus in small spaces

The sweet smell of its blossoms, glossy dark-green foliage, and brightly coloured fruit combine to make citrus one of the most ornamental and useful plants you can have in your garden. Just about every type of citrus is outstanding in this regard, with both fruits and foliage being useful in the kitchen. The abundance of aromatic oils in most parts of the plant means that even the fruit rinds can add that special touch to recipes.

An interesting thing about citrus fruits is the way they have evolved in cultivation in much the same way as domesticated animals, such as horses and dogs. Even though the original wild species of citrus come from Southeast Asia, some of the most popular cultivated types have exotic names, such as the Palestine sweet lime, Tahiti and West Indian limes, and the Lisbon lemon. These names reflect the fact that these varieties have arisen in cultivation after the various types of citrus were distributed to far-flung corners of the globe in the course of human history. The geographical range of these exotic-variety names is also a testament to just how adaptable this group is to an array of climatic conditions. Their only major weakness is a susceptibility to heavy frost.

Although some of the citrus group, such as oranges, lemons, and grapefruit, can grow into substantial trees, others, such as mandarins, cumquats, and limes, are much smaller; making it possible to grow these types in large pots. This is by no means a new concept: In Europe in the 17th and 18th centuries, elaborately constructed greenhouses known as orangeries and limonaias were heated to overwinter the frost-tender citrus family. Louis XIV created the most famous of all orangeries at Versailles, where the lemon trees were grown in solid silver tubs, an idea that would certainly make a statement in your courtyard garden. Fortunately, in most parts of Australia and New Zealand, there’s no need to lug big citrus pots around in winter –  they can tolerate the light frosts that most gardeners experience. If you live in a very cold climate, grow them in a protected spot, such as within a courtyard or beside a wall.

Try these on for size

When growing citrus for small spaces, possibly the best are the Nagami, or oval, cumquat (Fortunella margarita) or the Marumi, or round, cumquat (Fortunella japonica). You can consume the tiny fruits of these attractive plants whole or use them in various culinary pursuits. Both species grow to only a couple of metres; therefore, it’s easy to grow them in even a moderately sized container of, say, 25-30cm diameter. Cumquats also lend themselves to the formal look of a standard (i.e. a plant that is shaped into a ball or is allowed to spread out at the top of an elongated stem), which you create by allowing the leader stem to reach a height of 1.5 to 2 metres, then pinching the growing tips every few weeks during growing season to make a spherical shape.

The lime (Citrus aurantifolia) comes in a number of varieties, all growing to approximately 4 to 5 metres. Tahiti, or Persian, limes boast relatively large fruit, whereas Mexican, West Indian, and Colombian sweet limes have smaller fruit with stronger flavour. The attractive-lobed, shiny leaves of the Kaffir lime are highly prized as an essential flavouring for Thai and other Asian cuisines. It’s also one of the best to grow in a pot, and its glossy green leaves look particularly attractive – almost too good to eat!

The mandarin (Citrus reticulata) is another of the more compact citrus species, growing to a manageable 3 to 4 metres. Although Imperial is perhaps the hardiest of the mandarins, Ellendale has tasty, sweet fruit, and Clementine has proved to be a better performer in cooler climates.

Another option for growing citrus in small spaces has come about through the introduction of a special rootstock, Flying Dragon, which limits the size of citrus varieties that are grafted onto it to a far more manageable size for small gardens, courtyards, and balconies. This extremely useful rootstock dwarfs all types of citrus, so even the taller growing types, such as lemons and oranges, can now fit in a courtyard garden. The fruits are still the same size, but the plant’s height and width are reduced.

Fragrant and flowery

The tantalising taste of the various citrus varieties is reason alone to grow them. However, these fruits also tempt another of our senses with the heady perfume of their white starry flowers. Most types flower in spring, then develop fruit through summer. This is a crucial time to keep them evenly watered through regular irrigation (say, one deep watering a week) and a 10cm layer of mulch, such as Lucerne hay. It’s important to keep the mulch away from direct contact with the trunk to prevent fungal problems such as collar rot.

Citrus fruits of all types benefit from a light trim in late winter to keep them compact and bushy. You can prune back stems up to the thickness of your index finger, but I don’t recommend this unless the tree is really in need of reshaping.

The most common pest problem is leaf-miner during the warmer weather, so be on the lookout for leaves with a scribble pattern on the surface. It occurs mostly on fresh new growth. You can pinch off affected leaves to prevent the problem from spreading. Scale insects and aphids feeding on the leaves and stems are other common issues with just about every type of citrus; often, black, sooty mould growing all over the plant indicates their presence. By eliminating the sucking insects, you can stop the sooty mould. Using horticultural oils, such as pest oil, is a very low toxicity way of controlling these pests. Spray as directed onto the stems and both surfaces of the leaves during the cooler parts of the day.

Feeding your fruit

For citrus in large containers, use a potting mix designed for this purpose, such as a terracotta-and-tub mix, which not only holds plenty of water, but also gives the roots the good drainage they need to thrive. As far as fertiliser goes, the diluted liquid from a worm farm or a few good handfuls of well-rotted cow or horse manure can keep your citrus glossy and dark green. If you don’t have access to these organic options, it’s a good move to sprinkle controlled (slow) release fertiliser evenly on top of the mix once in early spring and again in late summer to keep the plants growing well. You can also fork water-storing granules into the mix if the plants are drying out excessively in the summer months.

If you can keep up the watering of your citrus through the hot summer months, you’ll be richly rewarded with juicy, tree-ripened fruit that will make a world of difference to your fruit consumption and culinary pursuits.