Monday, April 29, 2013

An edible forest garden

Back in March, Susan and I did a weekend course in Melbourne with US edible forest garden expert Dave Jacke. A fun, informative weekend it was too: Dave's knowledge of all things edible and forest-dwelling is remarkable. His two-volume work Edible Forest Gardens must surely be the most detailed, informative book on the subject yet written.

But what is an edible forest garden?

An edible forest garden is an example of ecosystem mimicry. Observing a complex, self-sustaining forest ecosystem, understanding its key elements, interrelationships and processes and attempting to replicate them using plants which are human food crops.

At its most basic, a forest ecosystem might comprise:
  • canopy layer – tall trees that need full sun
  • understorey layer – smaller, shade-tolerant trees and shrubs
  • herb layer – herbaceous perennials
  • groundcover layer
The idea of edible forest gardening is to fill all of these niches with plants that are edible or otherwise useful to gardeners, and to do it in such a way that competition is kept to a minimum and mutually beneficial (symbiotic) relationships are maximised.

That's a very rudimentary attempt to describe the theory; now for the practice!

A year ago Jill and Mike removed four cypress trees from their garden, leaving a grass-covered space about 20 x 8 metres. That much real estate right next to The Patch was not something I could ignore, and so I came up with various ideas to fill it, including a large polytunnel and various animal husbandry schemes more suited to a 10-hectare farmlet, before hitting on the idea of … you guessed it: an Edible Forest Garden. Henceforth known as the EFG.

Jill and Mike have been good enough to indulge my new passion, and we're starting on the EFG this winter. Here's a plan showing what the EFG should look like after about 8–10 years:
Click image for a larger version
The coloured circles represent the trees and shrubs. Informal bark paths provide access for harvesting (and wandering around) and also break up the area into patches, each of which will be dominated by one or more combinations of herbs and groundcovers.

The choice of trees and shrubs was determined to some extent by what's already in Jill's and Mike's garden: they have a wide variety of fruit trees, and there seemed little point in planting more of the same. Carob is a stately, pyramid-shaped evergreen tree from the Mediterranean area and will increasingly dominate the site visually. The design mimics an open woodland rather than a closed-canopy forest, with the tree and shrub layers covering less than 50% of the area.

When selecting the species I also attempted to bring together plant communities that would work well together and to this end I compiled a table with the key characteristics of the species I was looking at.

It will be interesting to see how far the reality of this Edible Forest Garden comes to resemble the plan!
Click image for a larger version

Sunday, February 24, 2013

The Patch update - 2 years on

It's been nearly two years now since we started work on the Patch - our 600m2 Landshare garden at Jill's and Mike's. I thought it was time for an update on what we're growing this summer.

The central part of the garden is 8 beds of annual veggies, grown on organic principles. We only have hand watering, so the beds need to be moisture-retentive and well mulched. The perimeter is much more permaculture based, full of diverse perennials, and will continue to evolve and grow in richness and diversity year on year.

Pumpkin bed

The pumpkins (var Anna Swartz) are growing strongly in a deep mulch of seagrass over home-made compost (mostly carpet weed from the Patch with grass mowings and horse manure).

Three Sisters bed

The Three Sisters are maize, a cucurbit and a climbing bean. Growing these crops together is a Native American method of preserving soil fertility and getting three useful crops from one patch of ground.

This year I'm experimenting with growing the maize in 1.5 metre cylinders of rabbit fencing. This provides support for the tall plants on windy days and also a framework for the cucurbits (lemon cucumber and rockmelon) to scramble over.

I've chosen small, less vigorous cucurbits: big bruisers like pumpkin and zucchini tend to go berserk and crowd out the other 'sisters'.

Potato bed

We grew Desiree and Dutch Cream under a deep mulch of pea straw. We're harvesting good crops from this bed. With the weather being so dry (only 50 mm rain since the start of November) we have been able to leave the potatoes in the ground and just harvest what we need. If it ever rains properly again (!), I'll need to dig up the rest pronto before they start to sprout.

Root veg bed

root veg bed in late spring
In this bed we mostly sowed Globe beetroot, Hollow Crown parsnips and a few carrots. There was also a row of long-keeping brown onions - root veg and onions make good companions as they feed from different depths in the soil, are both light feeders and the leafy tops of the root crops provide good shade for the bare soil (I don't mulch onions these days, to avoid problems with onion rot). The beetroot have been huge and sweet enough to eat raw.

Globe beetroot

Onion and carrot bed

You can never have too many carrots. Ours were a French heirloom variety St Valery, deep orange in colour, sweet and often 30 cm long. Yummo!
St Valery carrot
We also harvested a great crop of Early Creamgold long-keeping onions and Barletta salad onions and four varieties of garlic. Half of this bed is now growing Listada di Gandia eggplants and orange capsicums.

Early Creamgold onions
Part of our garlic harvest

I've left a few carrots and onions in the ground to flower. The ladybirds, hoverflies and bees love them and they look great too.

Carrot and onion flowers in the early morning light

Amaranth and cape gooseberry bed

Amaranth produces copious amounts of grain-like seed. The plants grow to two metres and are quite drought tolerant. The flavour is a little like quinoa but the seeds are much smaller. Apparently you can pop them as a breakfast cereal. I must try this.

Amaranth
Cape gooseberries are juicy, vaguely citrus flavoured sweet berries in their own little papery 'Chinese lantern' protective hulls. They're an undemanding crop and the fruit keeps well.

Watermelon bed

This year we're growing Moon and Stars watermelons. So far I've only found a couple of tiny melons, but they tend to hide away under the foliage until they're improbably huge. Last year we ended up with four monster melons with sweet, juicy, dark red flesh.

This bed also has climbing beans but they seem to have been hit by some kind of virus. The leaves are distorted and the affected plants have not flowered. Must get to the bottom of this problem but I frankly haven't had time to investigate further.

Tomato bed

This bed is producing quantities of Tommy Toe, Periforme and Amish Paste tomatoes. Those Amish sure do know a thing or two about tomatoes!

Tomato bed in late December, showing sturdy bamboo frame (2 metres tall)

Permanent plantings

We have perennials all round the perimeter of the annual beds. On the west there's the comfrey bed, which also has globe artichokes, goji and chokeberries, lemon verbena, Queen Anne's Lace, lavender, rosemary and a few tree onions. There are also some borage plants, which I'm hoping will self-seed everywhere, and a couple of echiums. Our Warré beehive is also in this bed and the bees seem pretty happy there.

Bee hive amid the artichokes

On the east is the lucerne bed, which we plan to increase to 60 m2 in the autumn, to provide nitrogen-rich mulch to the annual beds and great long-lasting summer forage to the bees. The lucerne receives only natural rainfall (precious little of that this summer) but keeps going strong through the hot weather. The weeds just can't compete. There's a tricky, sandy patch where even the lucerne hasn't taken, where I'm planning to try the drought-tolerant (and strangely named) barrel medic, a legume related to lucerne but allegedly even tougher.

On the south side there are a few flood- and drought-battered lavender bushes and a fig tree. This area needs improvement and a few creative ideas.

On the north side is our wattle windbreak which is starting to bush up now after a tough start in life. There will also be coastal rosemary and saltbush in the windbreak, and in the lee of that there will be a Hügelkultur mound which will hopefully be home to acid-lovers like blueberries and strawberries next year. A swale should help to hydrate this area and should become home to some of the frogs and lizards which are plentiful in the garden.

I just need the hot, dry weather to break so that digging a 12-metre long, metre-wide and half-metre deep swale by hand is less of a daunting prospect!