Gardening Weather at Last!

Down the side of my driveway is a gap to the fence of no more than 15cm, as deep as the slab.  The gap had nothing in it at all except weeds, and I thought I had no soil to put in it until I remembered the unused planter box mix sitting in a heap near my Hill's hoist.  We weeded, then I barrowed the planter box mix to the driveway and the kids swept it into the gap.  When we were uncovering the mix, we found a nest of blue ants with their eggs.

At every fence-post, the Sprig planted Dietes grandiflora, which I had divided from a clump in the front garden.  The clumps are shallow-rooted in my clay soil but were very hard to dig out because the clump was a good half-metre across.  Dividing the clump took a while too as I hadn't tried it before.  Dietes is a great plant for Sydney, growing in a slow-spreading clump of strappy leaves to 60cm and requiring no attention whatever.  The flowers are of the iris type, with a purple 'cup' over a wide white 'saucer'.  Unfortunately, these wilt quickly when cut.

At the shady end of the long bed, the Sprig strewed forget-me-not seeds.  I popped in a Pelargonium where we will see it from our family-room window, then planted rooted segments of Coleus amboinicus up at the sunny end.  Near our pond garden, I found a baby Erigeron karvinskianus growing, and I've transplanted this to the driveway bed too.

The native violets I bought the other day (with the sweet peas and bugle flower) has gone under the little bracelet honey-myrtle by the pond.  The sweet peas are planted around two tetrapods in the herb bed.  I've also planted the blugle flower there.  I have a feeling it is Ajuga reptans 'Cavalier' rather than the Ajuga reptans purpurea on the label: the cultivars were mixed in together and mine has large purple leaves rather than small ones.  I thought the Ajuga would look good next to the Echium because of the contrast in foliage, and I do hope the bloom periods overlap:  the bugle flowers are the same shape and colour as the Echium's, just much smaller.

Ixia viridiflora are a turquoise colour with a purple-black central eye, so I thought they'd go well with my mallard-green pergola.  I've planted them around the bugle flower.  There are now half a dozen Allium 'Drumstick' bulbs at the back of the herb bed too. 

The peacock flower, Moarea aristata, has snow-white petals with a navy-blue stain at the base.  I thought they'd look nice near my rosemary (which has a deep blue flower) and marjoram.  At the other end of the bed, I have planted deep velvety purple Sparaxis so one day they will flower near a pineapple sage (not yet purchased).

Then I've started a row of 'Greenfeast' peas near my washing line and am soaking some snow peas for planting on one of my tetrapods in the herb bed.  The other tetrapods have sweet peas around them. The only harvest in prospect is of small tomatoes, but they are delicious!

March Garden Update

It hasn't been a good summer for a gardener, and I'm a bit disheartened at the dreadful state of my garden (not helped by a number of family crises which reduced my gardening and blogging time considerably!). Here's a quick tour.

These are some of the few tomato flowers I've seen, on a "Broad Ripple Yellow Currant" that I planted in January. In November I planted "Brandywine" tomatoes and now there are two large but green fruits on one plant. That is all.


I've had a few cucumbers, but not anywhere near the number I expected. Hoping there are some still to come.


The frequent rain has kept my banana suckers happy, though!


The chicky-babes have grown up a lot. This was how they looked in mid-March, at a month old.


Ages ago I planted some Swamp Foxtail grass down the back of my garden, but it was overshadowed by a grevillea. Now the grevillea is senescent, we can finally see the grass which marks the end of the bed.

Return of the Hill's Hoist

That black stake towards the right is important. It is an X that marks the spot.


A day after I hammered it in, our builders replaced it with my old Hill's Hoist. I hadn't realised how big my clothesline was until I measured it -- each arm is eight feet long ( I would have guessed six feet), giving it a diameter of 5m. You need to allow at least a metre from any obstructions such as fences, so that your sheets can fly out in high winds without snagging.


Suddenly, my back yard feels more homelike, more like my little bit of postwar Australian suburbia. But not entirely. Here's a shot (taken by one of my children) of the Hill's Hoist in its original, convenient location: in line with the back door and close to the house to save steps.


The people who would have lived in my house first would not have ever had a back garden. They had a back yard, used for drying clothes, growing vegetables and fruit, and keeping chooks. These were not things you invited visitors to see, hence the prime location of the clothes-hoist.

These days, we cherish our outdoor time as our jobs are sedentary, and want to show off our back yards. Yet I still wanted the Hill's Hoist, so where could I put it?

My vegetable patch seemed to be a little too hot in summer: I had problems with plants suffering sunburn and dehydration. I'm moving my Hill's Hoist there, into a spot where it won't block views from our new doors. The vegetable garden will be closer to the house and water tanks, but you'll have to stay tuned for more about that.

Bifold Doors and Chokoes

We have reached lockup stage now. All our doors are in, including the bifolds for the family room. Aren't they lovely?


In winter, the sunlight will stream in to warm the slab in the family room. In summer, the pergola will be covered with vines for shade. In fact, I already have a choko (chayote to some) growing on the windowsill towards next summer. My long-term plan is for a passionfruit vine to cover the pergola, but even if I plant one as soon as I can, there won't be enough of it to provide shade this year. The choko vine, however, will be luxuriant in months.

The choko vine and the passionfruit vine are staples in Sydney, though chokos -- traditionally grown over one's shed -- are much less common than they were. The newer dwellings don't have enough space for a choko vine, for one thing, and secondly, a lot of us grew up eating chokoes way too often! I saw some nasty big yellowish ones at the shops today for $3.99/kg, way too much, and at least twice as big as they should have been. Of course, the one I bought was even worse: I could see it was starting to sprout, which was why I wanted it! I don't understand why greengrocers persist in selling such old chokoes.

I saw the aggregate and the planter box mix being wheeled in this morning to fill the herb bed, but I can't really plant my choko until the pergola is painted. I might sneak in a few late bulbs, though. Or if I can find my strawberry plants... if they've survived... I might pop them in.

Garden Wreckage

Builders, even nice builders like ours, inevitably damage a garden. Machinery and goods have to be moved in and out, new drainage lines have to be dug (Oh! Farewell, Salvia 'Black Prince'! sob). We also had a huge new pit drain installed, which ran further under my vegetable patch than I realised. I knew its length; I hadn't realised the width! In the left foreground is a mound of reasonable soil from the vegetable patch, taken from the drain area. The bare earth on the right-hand side is mostly clay.


And the only thing coming through the clay is onion weed.


Apart from the occasional nasturtium and borage.


My damaged and unmaintained vegetable patch, however, still has a few surprises. The leeks and red silverbeet are still going, along with the sorrel and a Tuscan kale. I wasn't surprised to find volunteer parsnip everywhere, because that's what parsnip does. What did surprise me was the chervil on the far side of the garden, and feral Florence fennel everywhere!


The other surprise is our sneaky Banskia spinulosa. This plant has been sitting there for years, refusing to flower, growing nicely but not a "candle" in sight. But now we aren't looking at it, what has it decided to do? Hmph!

But in my garden?

While I have been regaling you with photos of Victoria, not a lot has happened here in the garden. It has proved difficult to plant warm-weather crops as the last few months in Sydney have been extraordinarily wet; in fact it's raining right now.

Month	Average (mm)	Actual (mm)
September	52.7	69.8
October	64.9	85.2
November	72.9	108.0 (so far)

This is due to a fairly strong La Nina effect which is expected to remain all summer. Our summers are when we receive most rainfall anyway, but we'll probably have longer rainy periods rather than storms. I will also be expecting more moderate temperatures. While that's good for the vegetable garden, the humidity won't lift so often (generally the humidity drops when we get over about 30C), which tends to mean problems with mildew.

The trip to Melbourne, enjoyable as it was, put a hole in my vegetable planting programme. Since then, it's been hard to find time when the soil is dry enough to allow planting. This weekend, fortunately, gave me both moist (not puggy) soil and time. And now my new plantings are being watered in!

Yesterday, in went my six 'Brandywine' tomato seedlings. I am hoping that temperatures will stay cool long enough for them to grow and set fruit; they should have been in the garden at least a month ago! I am planning a second planting of 'Brandywine' for autumn tomatoes -- in fact, I should plant the seeds this afternoon so that they fruit in March.

The tomatoes are now surrounded by basil, 'Mini' cabbages, 'Flame' lettuce and some 'Mini White' cucumbers, and a row of 'Stringless Pioneer' beans.

Today I planted a block of Sweet Corn 'True Gold' underplanted with Cucumber 'Lebanese Mini Muncher' and 'Sugar Baby' watermelons.

Yesterday, I also put in my heirloom beetroot seedlings, and radish 'French Breakfast' near the bolting Florence fennel and 'Tuscan Black' kale. Found that my leeks had survived, which was rather a surprise. They are sheltered by a sorrel clump and a bolting parsnip, and so should cope when it gets hotter.

My quince tree is laden with small quinces. I need remove a lot of them, then bag the rest against fruit fly. Underneath it, however, are some impressive volunteer tomatoes, which also need bagging. I hope I don't damage too many of them!

By all reasonable measures (that is, non-calendar ones), it's summer:

• The jacarandas across Sydney have passed their peak of bloom
• Blowflies and mosquitoes have appeared
• We have heard Greengrocer cicadas in the trees
• The Ashes have started
• The air-conditioning at my workplace broke down
• The shops are full of Christmas things
• Our Christmas tree went up this afternoon
  

And I'm off to prepare my Christmas cake fruit right now: it has to macerate in brandy overnight before I bake the cake tomorrow. See you later!

Pea-Tunnel

Colleen Vanderlinden posted last year about a cucumber trellis she saw at the Michigan State Fair. She has a great photo of it, and I've been wondering how to do something similar here.

Then, as it happened, I ended up with two rows of peas planted next to each other.

I think they'll meet at the top eventually, so I'll keep you posted (they've doubled in height since I took this photo last month). In the meantime, we've had platefuls of fresh peas gracing the dinner-table several times, an experience that only gardening can buy.


Even better -- those peas in the front are 'Purple-Podded Dutch'-- with pink flowers. I can't wait!

Another List of Gardening Activities

One day, my horrible garden sheds will be demolished, which means that the contents have to go somewhere else.

Have you ever looked at your garden shed and contemplated having to pack it? It occurred to me that disintegrating bags of lime and blood-and-bone are not packable, so I did something radical on the weekend... I used them up! The lime went on my vegetable patch and the native plants got the blood-and-bone -- it's their favourite fertiliser.

The Geek and I put up some more pea-netting and the Sprig helped me plant 'Purple Podded Dutch' peas under it. I'm still deciding where to plant the snow peas, as I never have much luck with them.

The new pea-netting used to hang at the back of our house, where I had a small brick-edged garden bed and a 'Nelly Kelly' grafted passionfruit. Now I don't know if this happens with all of them, but the stock suckered unstoppably and inevitably the graft died off. The stock has been going strong for years (still suckering madly), but it doesn't produce edible passionfruit. The same thing happened to Dad's 'Nelly Kelly', so I won't buy one again unless someone gives me a very good reason. But with the wall slated to become an interior wall, there was no reason to waste my netting on an ugly stock any more, was there? And those bricks could be reused, so out they came. The boys had a lovely afternoon building with them.

My cut finger has prevented me from planting up punnets for a couple of weeks, so I turned to that next. I had to plant out a few beetroots and cabbages, and found that the bed was full of volunteer lettuce and bok choy seedlings -- which is great, seeing as I have missed out on planting those things recently!

Seeds planted:

• Beetroot 'Globe Free' and Heirloom Mix
• Cabbage 'Mini'
• Florence Fennel
• Kale 'Tuscan Black'
• Leek 'King Richard'
• Lettuce 'Yellow Leaf' and 'Forellenschuss'
• Onion 'Borrettana'
• Pak Choy 'Red F1'
• Silverbeet 'Five Colour'
• Spring Onion 'Evergreen'

The one thing we didn't get to was building a teepee out of the pruned branches you see at the top of the post. Next week...

Winter Evening

It's still early winter here, and all the plants seem sleepy in the evening light.

This reddish tint is not the light: it is Red Pak Choy, just about ready for stir-fry.















Broad beans coming up with celery and parsley -- a typical scene in my deliberately disordered vegetable patch.


I am not sure what to do with my Brandywines -- they're still flowering, but I doubt even the big fruit will have a chance to ripen. Should I pull them, hang up the vines and wait? Or turn them into fried green tomatoes?






Lizzie and Annie have been escaping from their winter quarters, so I had to improve the security today. Turned out that Lizzie was squeezing through a gap in the netting -- that's where the board is.












My husband had to cut the wattle back (to the right you can see one of the Parramatta Wattles which grew bigger than expected) so that it wasn't blocking quite so much light to the solar hot water system.













Cutting back the wattle led to cutting back the mulberry tree. We are planning to make a teepee or something with the branches, once the leaves fall off.


















Thyme and sage in the 1950s fake log trough (including frog) which I found in the garden when we moved here. So much of my life in the background: the washing, the chook dome...

What We Did Yesterday

It is amazing what the extra time on a long weekend allows you to do.

On Saturday, the Geek and I prepared our bathroom for painting. The Geek was able to put two coats on it yesterday and it was dry in time for the kids to have a bath. Turns out that the Geek's long arms enable him to clean and paint all the bits of the bathroom which I need a ladder to reach. So I cleaned the bits I could, used the Spakfilla, and cleaned stray paint off the tiles afterwards. Our next project is attaching the medicine cabinet.

Our bathroom now looks almost as I want it to. We have a timber vanity unit that looks like it was made in the 1930s, which suits our house. The dark sage-green wall tiles have a border of gum leaves at head height. Above is the lighter sage green paint. The floor tiles are a medium brown. Our tapware is chrome with the old-fashioned, comfortable cross handles, and the basin and bath are white.

While the Geek was painting, I kept the boys occupied in the garden. We had moved the chooks along in the garden, so half the vegie patch was ready to plant. The boys cleaned old vines off the wire trellis for the peas, and I rehung it. The boys did the planting of 'Greenfeast' peas, though. The Sprig planted some carrots, and the Twig the broad beans. I did the seedlings, however, and sowed some new punnets of winter vegetables.

The Twig and I moved the strawberries into the vegetable garden as mentioned, and planted their trough with sage and thyme. I also potted up some Allspice Plant (Coleus amboinicus, but it has many common names) to sit next to my aloe-and-dichondra pot.

Another big job, where the boys were a real help, was to remove an old weeper hose from under the fruit trees. We didn't quite finish laying the new one, but then, who does finish all their planned garden jobs in a day?

Portrait of Autumn

It's my favourite time of year for gardening, so felt a sudden need to buy a few things at Bunnings on Friday. Today I set up a terracotta pot combining Aloe vera and Dichondra argentea. I've admired this Dichondra for some time on Digging and now have it in a combination which I'm happy with. It will live in a sunny spot under our carport roof.

Then I decided to plant my 'Nelly Kelly' blueberry in a big self-watering pot, which had been holding tomato stakes for a while. There was a lot of leaf litter in the bottom of the pot (and perhaps redbacks), so I tipped the pot sideways to clear it. Next thing, something had leapt out of the water reservoir! The frog then sat still in an I'm-not-here fashion, so my children were able to have a look at it too. Given its size, I think it might be a Pobblebonk, rather than the Common Eastern Froglet or Brown Toadlet. I made sure I replaced the pot in roughly the same spot and am hoping that Jeremy Fisher returns to his home. I am also hoping that 'Milkmaid' nasturtiums grow true to type as I've put some seedlings from last year's plants around the blueberry.

Tomorrow, I'm moving my strawberries into the vegie patch and planting the empty trough with sage and thyme. It occurred to me that these plants would probably do better in a cactus mix, so we'll see if that improves their lifespan. I'm good at killing thyme and sage, alas. Then there are a few other vegetable seedlings to transplant, carrots for the Sprig to sow, and a bathroom to paint...

Listada di Gandia

If anyone speaks Italian, they can tell me the correct preposition: you'll find it sold with de, da or di as the middle word. At any rate, it is a beautiful eggplant. I picked this one today, but I'll have to develop my ripeness sensor -- it's still green. Taste test results to follow.

Tomatoey Thoughts

We had a lot of rain last week, and this cracked 'Brandywine' was the result. It had to be eaten right away, but still tasted wonderful. They really have an excellent flavour and I like the pink shade, too.

The real problem is in cultivation. 'Brandywine' is from North America and is (I think) named after the Battle of Brandywine Creek, in Pennsylvania. If it was developed in this area, it is not really adapted for Sydney conditions. I should have realised from the potato leaves that the plant was adapted for lower temperatures and light levels: my plants are horribly burnt. The fruit fly bags have protected the fruit from scorching, but fruit set has been poor. The average tomato plant, according to Malcolm Campbell, will set fruit as long as there are periods below 27 C during the day. I suspect that the 'Brandywine' might stop setting fruit at something closer to 24 C, or that it prefers lower overnight temperatures -- our minima rarely fell below 20 C in January. I plan to keep growing 'Brandywines', but in future I will plant them early and late in the season. If anyone has ideas on what would be a good mid-season tomato for Sydney, I'd like to hear about it. My Dad used to plant 'Grosse Lisse'.

I'm completely unimpressed with 'Tommy Toe', after two years of growing it. I'm used to rampant cherry tomato plants which just appear as volunteers and produce trusses of yummy fruit. 'Tommy Toe' takes ages to flower, and then only gives you a couple of tomatoes at a time. Worst of all, they don't have much flavour. A big thumbs down to this one.

The other variety I grew this year was 'Principe Borghese', which are small "paste" tomatoes, used in cooking and for sun-drying. I managed to sun-dry some and they taste fine, but I prefer fresh tomatoes. Worth the experiment, but I probably won't bother buying the seeds again.

How about you?

Simply a List of Seeds

I have found I don't need to buy any seeds for winter crops; I seem to have everything! So here's my complete list. Most have come from the Digger's Club.

• Bush Beans: 'Yin Yang'*, 'Green Stringless',and 'Stringless Pioneer'
• Beetroot 'Globe Free' and Heirloom Mix
• Broad Beans 'Aquadulce'
• Broccoli 'Romanesco'
• Cabbage 'Mini'
• Capsicum 'Mini Sweet' mix
• Carrot 'Mini Round'
• Celery (collected here)
• Coriander, Chervil, Dill, Rocket
• Cucumber 'Mini White', 'Lebanese Mini Muncher' and 'Lemon'
• Eggplant 'Listada de Gandia' and Heirloom mix
• Florence Fennel
• Ground Cherry 'Aunt Molly'
• Kale 'Tuscan Black'
• Kohlrabi
• Leek 'Elephant' and 'King Richard'
• Lettuce 'Flame', 'Yellow Leaf' and 'Forellenschuss'
• Onion 'Borrettana'
• Pak Choy 'Red F1' and green type
• Parsnip 'Hollow Crown'
• Pea 'Snow Climbing', 'Purple Podded Dutch' and 'Greenfeast'
• Pumpkin 'Queensland Blue'
• Radish 'French Breakfast' and 'Easter Egg'
• Silverbeet 'Five Colour'
• Spring Onion 'Evergreen ' and 'Red'
• Sweet Corn 'Golden Bantam'
• Tomato 'Broad Ripple Yellow Currant', Tommy Toe', 'Principe Borghese' and 'Brandywine
• Watermelon 'Golden Midget'

When did I find time to do this? It's been raining, so I haven't been in the garden. Summer rain in Sydney can have a tropical intensity. We've had over 150mm since Tuesday, which is one-and-a-half times the monthly average... and it's only the 7th!

* Alas, the packet is marked 'Ying Yang', which in Australia, at least, means something different.

Another Man in my Life

Well, it was only a brief encounter. He joined us for dinner.

Yum Yum Yum!

I know there are better-looking tomatoes, but our first Brandywine tasted fantastic!

Is it Obsessive...?

We had a bit of light rain on Christmas Day, enough to dampen the ground. But with a few days of rain and cool weather forecast, it was obviously the right time to plant my advanced vegetable seedlings. So there I was on Boxing Day morning, rain on my back, hurrying to get my plants into the ground. Pumpkin 'Potimarron' under the quince tree, then a few heirloom tomatoes, capsicums, shallots and lettuces into the main garden. I think I only reached 'obsessive gardener' status when the rain started to run off the tip of my nose.

What do you think?

Summer Vegies

The erratic heat and cold of September delayed my summer plantings by nearly a month, but now, there are four 'Brandywine' and four 'Principe Borghese' tomato plants growing happily in the vegie patch. They are just starting to put out flowers, with the 'Brandywine' buds looking decidedly larger than the usual tomato flower. Various fast-growing plants that I planted between the tomatoes, such as basil, pak choy and lettuces, have been badly chewed by snails. I think it's time to open the snail pub.

The first sowing of beans are about to flower; they were planted about three weeks ago next to the Brandywines, as you can see above. The second sowing will be up in a few days.

My cherry varieties,'Broad Ripple Yellow Currant' and 'Tommy Toe', are also in and flowering. But I have a little problem. Where do I put my other tomatoes, the mixed heirlooms?

A more serious problem is the mysterious white leaf that has appeared on one Brandywine:


It looks worryingly like iron deficiency, and I've given the plant some seaweed tea. There isn't much you can do for iron deficiency, I understand, as tomato plants don't like lime much. I might be driven to adding lime if the problem continues.

The boys were unimpressed to see me planting lots of squash seeds, but the seeds were in fact out of date. If I get any squash plants, that will be nice -- if not, that's fine. The boys have also planted some 'World's Largest' pumpkin seeds, so we'll have to see how they go -- they aren't up yet. They are segregated under the lemon tree. I'm hoping my 'Turk's Turban' pumpkins, under the quince, will produce as they are so beautiful. To my astonishment, I discovered that my rhubarb there has resprouted. I thought the chooks had scratched it out!

A single cucumber plant has survived to grow up a trellis and flower. I can see teeny-weeny cucumbers on it.


Now I just have to figure out where to put all the seedlings I'm nurturing: more silverbeet, some salad onions, leeks, mini capsicums, eggplant, and ground-cherries. It is annoying that so many summer crops are Solanaceae; it's inadvisable to plant them in the same place each year, but I really don't have much choice (except to expand the vegetable garden...).

Awakening of Less Cheerful Feelings on Arrival Home

Such pretty flowers. They start as cerise buds, turn to purple flowers and fade to blue.


The problem is that it's Paterson's Curse, one of the worst pasture weeds west of the ranges! So what on earth is it doing in my back yard? My guess is that it came with the chook feed.

The native blue-banded bee likes the flowers, as did another smaller bee that moved too fast for me to photograph. Beekeepers refer to the plant as Salvation Jane, since it provides forage for bees during drought and produces a delicious honey.


This plant was only 30cm high (they grow to about 120cm), but the tap root was already 1cm thick when the Geek pulled it out on Saturday. We hope it will not resprout. I've never seen Paterson's Curse in Sydney -- it's an echium, and prefers a Mediterranean climate. There is a distant view of Paterson's Curse in a previous post.

I hadn't found a reason to cook this lovely beetroot before we left, but just had to pull it on the weekend as it was getting a bit too big. That's a four-cup teapot behind for scale. Still haven't worked out what to do with the beetroot!

How to Get Rid of Cabbage White Caterpillars

Gavin posted today at Simple Green Frugal Co-op on his adventures in dealing with Cabbage White caterpillars in his garden. I thought I'd put together all I know about the Cabbage White and what has worked for me.

Know Your Enemy

The Cabbage White butterfly, Pieris rapae, seems to be one of the commonest garden pests worldwide. The caterpillars feed on crucifers/brassicas, and have a particular liking for cabbage and broccoli. The caterpillars hatch from single eggs on the underside of a leaf, and stay on the underside until they become large, when they move to the top. They work their way from outer plant leaves to inner ones. Early signs of their presence are pinholes on outer leaves, which quickly become larger until leaves are skeletonised. Green frass (chunky caterpillar poo!) is sometimes visible. Once the caterpillars are in the cabbage heart or into the broccoli head, they cannot be eradicated without chemical use.

In Sydney, the butterflies are more common in the warmer months, and you can expect to see caterpillar damage once daytime maximums move past about 20 C (that is, more than half the year!). The lifespan of the insect is about a month, with the last generation over-wintering in cocoons. The butterflies find each other -- and egg-laying sites -- by sight.


Eradication

Forget it. Unless your country is killing Cabbage Whites as part of a Four Pests Campaign.


Prevention

A lot of people overlook prevention, but insect plagues don't just happen. They occur when there is a confluence of favourable conditions. Here are some ways to make the lives of Cabbage Whites more difficult:

• Encourage insectivorous birds. These tend to be smaller birds, so provide dense (even prickly) bushes for habitat, and compost your cat. Provide a bird-bath. If you have chooks, consider tractoring them in your vegie patch so that they can eat any caterpillars they find.
• Encourage predatory insects. Stop spraying general insecticides in your garden, and don't kill wasps unless you really have to (when they have inconveniently-located nests). Wasps feed the caterpillars to their young. If your brassicas support braconid wasp pupae, don't pull the plants out till the wasps hatch. Remember the bird-bath -- most predatory insects need water to drink.
• Hide the cabbages. Interplant them with other vegetables. Patches and lines of identical plants are too easy for passing butterflies to see.
• Look populated. Scatter white half-eggshells around your brassicas. Apparently, the butterflies perceive these as other butterflies, and head off to lay their eggs in a less populated area. The calcium from the eggshells is good for your garden.
• Get real. If you insist on growing brassicas in warmer weather, you will get caterpillars on them. Not only are the butterflies multiplying, the brassicas themselves are not as healthy as they are in cooler weather, and therefore attract more pests. As evidence, I give you the photo below of one of my winter-grown broccoli, which is entirely unmarked.
  

But I Want to Kill Them!

Go out in the early morning and you will find the caterpillars sitting on top of the leaves, usually near the ribs. Pick them off and feed them to your chooks, or throw them onto the lawn for the magpies as Gavin does.


That's Yucky! I Want a Nice Civilised Pesticide!

Probably the most appropriate pesticide to use is Bacillus thuringiensis, sold as B.t. or Dipel. These bacteria attack caterpillars only, nothing else, and Dipel is therefore permitted in most organic certification systems. According to the MSDS, it's about as safe as you can get with a pesticide. Now go away and get over yourself.