Except I can't. Despite growing salvias for nearly 40 years and having salvias blooming here all year round in reds, yellows, pinks, blues and the most divine purple, I know remarkably little about them. You don't need to know much to grow salvias.

My experience with salvias is simple. I see them in a catalogue or fall in love with them in a garden or a nursery, buy them, plant them and watch them bloom and bloom and bloom. I prune them now and then in winter, poke the hard wood prunings into the ground, about 30 centimetres deep and snap off most of the tops. And they grow, just about every one of them, so we now have hedges of salvias all from a single original plant.

A few months after planting I can't even remember their names, which probably got lost when I unpacked them anyway. The only things I really know about them are that I like the colours (blues, purples, reds and pinks for the most part, although there are white, yellow and orange ones as well), and that they are hardy and long flowering and tolerate frosts, which not all long-blooming drought-hardy perennials will do. But without a record of those names, I can't give them to you you're going to have to read the labels or the catalogue descriptions for yourself. Helpful hint: there are many, many, many to choose from. Hundreds, though you'll need to do a bit of catalogue searching to find more than 20 or so. But trust me within that 20 you'll find enough to fill the garden with flowers, and the birds who'll feed on them, all year round. Not the same bloom all year round, mind you, but there is no time of year when there aren't some salvias profusely in bloom.

Just now there are the rich, red, pineapple sage flowers blooming down by the shed where they are protected from the seven degrees of frost we've been having. I do know the name of that one, pineapple sage, with richly scented leaves as well as about six months of flowers each year.

There is fruit salad sage too, with giant sprays of pink blooms, also in a frost-protected area. I have cut down the two blue salvias that flower outside my office, and which will put up new lime green growth in spring, and then in late spring and right through summer begin flowering until early next winter. The even richer blue salvias in the top garden have finally taken a break from flowering, as have the giant stems usually topped with the most intense purple flowers you have ever seen. I bought just one of those five years ago and they have grown so fast, with so much good snapable wood, that they too are a hedge today.

That is the secret with tall-growing salvias. If the wood snaps you can plant it. And I don't mean even a proper "plant" in a dug garden, you just thrust it in the soil among the bracken or weeds. If there is a drought, perhaps one in 10 may grow anyway. If it's an even reasonable season, 10 out of 10 will grow and your garden and your friends' will soon be filled with them. Just one initial plant is enough.

For me though not taxonomists salvias come in small, medium and large. The large ones grow at the back of the garden, the mediums in the middle, in beds edged with garlic chives, and the small are garden edgers themselves, or even small beds around bursaria and other shrubs.

And they survive. A good season, of course, gives you more flowers and lusher leaves. But even in 2003's summer drought the ones I planted survived. They didn't grow much, but they did survive.

The first salvias I planted were from a Country Women's Association stall, though I didn't buy them. A neighbour had and she gave me some cuttings of hers. They turned out to be about 30 centimetres high with velvet furry leaves and orange flowers through mid-summer, when very little else blooms and nothing else at all in those drought years from 1970 -1983. Except for those. I looked out at the barren slopes of orchards that were only just surviving, and there in the foreground were the orange salvias, blooming, blooming, blooming.

They were slow growing at first well, who can blame them? growing without water on a bank that was mostly clay and builders' rubble. But some time about a decade ago, after 30 years of sulking, they began to grow faster and faster still. Tiny cuttings shoved into corners have grown fast too, so now I need to haul them out as they spill over the path and keep encroaching. To a salvia that hardy cement paving is hardly even a challenge, much less insurmountable.

The orange darlings grow equally well in full sun, dappled shade or the quite deep and almost totally dry shade near the house, where black snakes like to lurk in them one reason for hauling them out, as I prefer to see the snakes, especially if they are sunbathing in the warmth by the house. And no, I still don't know what that particular orange is, although I've hunted for it even among esoteric salvia collections. Each time I think, 'Ah, I've found it' the one I've found turns out not to be that one at all.

And, to be honest, I'm not an orange-in-the-garden person, except for oranges, mandarins, tangelos, cumquats, calamondins et al. Orange is only permissible if you can eat it. So I haven't ordered nearly enough orange salvias to see if I can discover it again.

I planted salvias in the "almost gravel and not much else" so called soil around my favourite bursaria, last year. They have been watered twice; had totally insufficient water and no feeding, plus the wallabies decided they liked salvias and ate them for two months straight, And then, wallaby like, rejected them. The wallabies here relish any new plant in the garden. They like the taste of novelty.

Luckily for the floriferousness of our household once the wallabies have had a munch for a while they lose their taste for salvias and go back to their favourites roses, peaches, young citrus leaves, Iceland poppies Grass is way, way down the list, but then we have little true grass here what looks like grass is an amalgam of native ground covers.

The salvias didn't flower last year, but they have grown a little this winter, and I suspect they will zoom along as soon as spring really warms up. And then if the catalogue description is correct we should have 10 months of the year of red and white lipped blooms, about 60 centimetres high, in a bird-filled cloud around the bursaria, with its birds' nests in its thorn branches and beards of lichen on its stems. It will be a glory of salvia.

If only I could remember which one it is.

This week I'm:

* gloating over the seeds I'm planting in the pots in a warm spot on top of the barbecue in the middle of the paving, hopefully frost free we haven't barbecued anything for about a decade but it makes a great spot to germinate seedlings;

* dreaming of the watermelons, pumpkins and cucumbers whose seeds I'm planting;

* spreading chicken wire over the bits of vegie garden planted with lettuce and radish seed to keep the lyrebirds off;

* and on the compost I spread over last autumn's leaves where I'll be planting the watermelons and pumpkins;

* thanking the bower birds for deciding they prefer chicory to broccoli leaves we have a lot more chicory than broccoli; and

* watching the weeds grow while the wombats and wallabies eat the grass. It is weed mowing time, to chop their heads off before they set seed.