URBAN FARMER:Protect your crop from cotton- tailed intruders

But Peter, who was very naughty, ran straight away to Mr McGregor's garden and squeezed under the gate! First he ate some lettuces and some French beans; and then he ate some radishes; And then, feeling rather sick, he went to look for some parsley. But round the end of a cucumber frame, whom should he meet but Mr. McGregor . . .

from The Tale Of Peter Rabbit, by Beatrix Potter

--

ALONG with offering shelter from wind and frost, one of the many advantages of a walled garden is that it generally does an excellent job of keeping out unwelcome visitors (not so much humans, it should be added, but rather animals such as badgers, deer, hares and rabbits). One of the disadvantages, however, is that if any of these animals do somehow manage to get in, they can be awfully difficult to get out again.

Already this year in the OPW's walled Victorian kitchen garden in Phoenix Park, gardeners Meeda Downey and Brian Quinn have had to resort to using reinforced wire netting to prevent a hungry badger from making nightly forays into the vegetable patch.

It worked, but not before the determined nocturnal visitor had feasted handsomely on the walled garden's new potatoes, baby beetroot and Florence fennel.

But now, just when it seemed that such night-time raids on the walled garden were a thing of the past, the two gardeners have discovered that they have a far more worrying problem on their hands.

Rabbits.

"We noticed something had been eating the lettuce and the spinach", says Meeda. "Half a row of young lettuce plants just disappeared overnight and there were big holes in the spinach leaves.

So we were trying to work out exactly what was doing the damage when Brian saw a rabbit running through the nearby celery plants. We think it might have squeezed through the bars of one of the gates during the night, or else sneaked in during the day when the garden is open."

"But, as a gardener friend pointed out," adds Brian resignedly, " the problem is there's rarely such a thing as just one solitary rabbit. If we allow them any chance at all to become established in the walled garden, it'll be overrun in no time. We need to sort it out quickly."

The gardeners are right to be worried, because rabbits are famed for the incredible speed of their reproduction.

From just three months old, the female is capable of producing several litters a year, with an average of six baby rabbits (also known as "kittens" or "racks") per litter.

Nocturnal and territorial by nature, rabbits are also voracious feeders (70-80 times a day) and will eat a wide range of leafy vegetables. That's particularly bad news for Brian and Meeda, because the walled garden, with its neat rows of succulent lettuce, spinach, kale, cabbage, cauliflower, celery and carrots, is herbivore heaven, or the lapine equivalent of a Michelin-starred restaurant.

Older gardeners will remember the days before myxamatosis, when whole fields of crops could be quickly destroyed by rabbits. Back then, in 1940s Ireland, the rabbit population was so abundant that the animals were also a much-valued source of protein for many families and were regularly shot, snared, lamped, netted, trapped or caught with ferrets (see irishfieldsports.com for more information).

My own father regularly went rabbit-shooting as a teenager in Wexford (he could skin a rabbit in 12 seconds) and the meat was used by my grandmother to make a nourishing stew.

But then the rabbit population in Ireland was almost destroyed by the deliberate introduction of the deadly disease myxomatosis in the 1950s, and they ceased to be a worry for gardeners or growers.

In the last few years, however, there seem to be definite signs of recovery, with many GYOers reporting serious problems with rabbit damage this summer.

So what's to be done? Ideally, gardeners and allotment holders should fence off their entire vegetable plot with a 90cm-high, strong wire mesh, but just like the OPW's walled garden, this is only effective as long as the rabbits don't gain entry (rabbits are great tunnelers).

Burying the bottom of the wire a few feet below the ground makes the rabbit fence more effective, and all the more so if you bend the bottom 15cm or so at right angles away from the boundary line. Make sure, also, that the gauge of wire mesh used is strong enough, as rabbits are capable of biting through the weaker types.

For those looking for detailed information on constructing effective rabbit fencing, there's a very useful downloadable PDF available from the British Forestry Commission (forestry.gov.uk).

It specifies that gardeners use "18-gauge wire (about 1.2mm diameter) x 31mm hexagonal mesh netting, and with no point along the fence lower than 0.75m". There's also an accompanying diagram on how to construct the fence, including information on suitable timber supports, etc.

Electric netting or electric wire fencing is yet another option that some GYOers may take, although it's more expensive and rabbits can sometimes chew through the wires.

But if and when rabbits do breach the garden's defences, what are the gardener's options? Some urban farmers may consider violent ones, as repeated rabbit damage can make even the most peace-loving gardeners surprisingly bloodthirsty.

But while rabbits have little or no protection under the Wildlife Act and are legally considered vermin, the ISPCA argue that effective fencing is the best option and that snaring or poisoning these animals is needlessly cruel.

If you think you have what it takes to trap a rabbit (they're elusive), then consider buying a dedicated rabbit trap (check out trapman.co.uk for more information).

The ISPCA suggest that the most humane thing to do with any trapped rabbit is to release it back into the wild, or, at worst, to have it put down by a vet.

Alternatively, if you don't fancy your chances with a rabbit trap, one allotment holder that I read of suggested "getting hold of a large, aggressive cat"', which is another gory but effective way of controlling the rabbit population.

Just make sure it isn't a fan of eating vegetables, like one cat I used to own.

- The OPW's Victorian walled kitchen garden is in the grounds of the Phoenix Park Visitor Centre, beside the Phoenix Park Café and Ashtown Castle. The gardens are open daily from 10am to 4pm

- Next week Urban Farmer will cover pruning summer raspberries

Fionnuala Fallon is a garden designer and writer