If your ground's not desperately dry, and you're in hope of some good downpours over the next month, you might want to start moving now.

If the skies are still very clear at night then early frosts are a strong possibility. Cloudy nights with a little breeze to keep the temperatures above the critical level is what would be ideal.

And if you're also moving the clumps with a good earth mass around the roots, then the transplanting shock probably won't be too desperate to cope with.

If the ground is still pretty dry it may pay to dig the hole first (generous) then add a bucket of water before infilling with the bottom layer of enriched planting soil. A drought at the bottom of the hole is less likely, then.

No, the ground's not dry any more. It would be the perfect time to move plants now - if only they weren't still flowering. I haven't got the heart to cut them down in full flower (nor would my family allow me, which is maybe more to the point). We will definitely have some frosts in November - but the soil below the top level should stay warm for quite a while.

Andrew, you don't say which perennials you want to move. For most of the common, tougher stuff you can move them pretty well any time over the winter apart from when there's a heavy frost - which is fairly infrequent these days. I'd wait for them to go more or less dormant and do it then. 'Putting the garden to bed' is not really a very meaningful concept as there's always something going on. It's more of a general tidy up and brief lull. I have trouble deciding when to mulch as it's inevitable that there will be something flowering or at least leafing which I'll have to work around.

There are two, well actually three processes.

One is digging up and moving established perennials (planted either this spring or last autumn). They should presumably be fine, especially (as vetivert8 says) I manage to take enough of a root ball with them. Nepeta nuda, Helenium autumnale and Gaura lindheimeri. They are still flowering, so I cannot move them for at least a couple of weeks.

The second is planting out perennials I bought from a specialist (Hardy's Garden Plants) in July. I transferred them into large(r) pots, to make watering easier in the drought, intending to plant them out in the autumn. They have grown very well and are flowering now, which is why I can't put them in their final homes for another couple of weeks. Late-flowerers such as Leucanthemella serotina and Salvia uliginosa, plus some more Gaura lindheimeri and Gaillarda 'Burgundy'.

The third is my order of perennials for autumn delivery, which still has not arrived, presumably as a result of the summer shut-off and general lateness of everything this year (I had the same problem with late delivery in the spring, which meant that the drought was already pretty much upon us when my herbs arrived). They are Anchusa azurea, Campanula lactiflora, Dictamnus albus, Hesperis matronalis, Limonium platyphyllum, Paeonia officinalis and lactiflora, Paper orientale, Salvia verticillata and Solidago. Ideally I would want to plant them in the ground (well-prepared well in advance with well-rotted manure) as soon as they arrive, which should be any day now. But I am worried that some may not survive the winter. Should they all be OK with a good mulch? Or should I pot up some in larger pots and keep them by the house or in my cold frame (very limited space) over the winter? Last winter I lost a Hadspen selection of Lobelia and some Monarda that I had put in the ground in the autumn, but then I had probably not mulched enough, and I did not realise that they were quite tender plants.

I live in Muswell Hill in north London, so I benefit from some, but not all of the London heat effect.

Andrew - I think you're worrying too much. The ones in pots can be transplanted any time as long as they get enough water to establish. The ones on order can go in as soon as you get them. The ones that are still flowering can be moved any time it's not frosty. In your area it is very unlikely there will be a problem with them getting killed by the cold. More likely to be killed by rotting off through damp. Be bold. I don't mean to be nosey but you sound either like a new gardener or as if you are used to gardening in harsher climates. I doubt whether you lost your lobelia and monarda through cold. Possibly you mulched too much and they got too soggy round the crown. Or they were just in an unsuitable place e.g too dark. By the way the Hesperis is not really perennial. It can go on for a couple of years but it's basically a biennial.

I mostly move or divide perennials in the spring, but most will tolerate autumn too. Anything in a pot can be planted in the ground now. Anything bareroot might as well be planted in the ground too.

Some plants definitely prefer to be moved in autumn, the poppies are an obvious one from your list. They are in full growth now and it is best not to disturb them in spring when they should be flowering. The Peonies too are best planted now. Are these going to be bareroot? Autumn is definitely the time to plant peony roots. Deciduous shrubs also prefer being moved in autumn, but again you can plant from a pot at any time.

Thanks for the advice. I am new to a big perennial/mixed border because for ten years I lived in the centre of town where I had a small garden with a mixture of annuals and shrubs but very few perennials and lots of pots which I moved round to fill every possible gap. I became an expert on exotics but knew little to nothing about perennial gardening.

We moved to this house in the summer of 2005 and still have not planted fully because we spent much of the first year clearing an overgrown and unattended garden and double-digging with well-rotted manure.

I am still concerned as to how I lost my lobelia and monarda last winter. I doubt very much they got too soggy round the crown because they were planted towards the top of a sloping border that gets very dry in summer - and stayed very dry last winter because it hardly rained. (Being London, it is clay underneath.) I have since been told that lobelia needs plenty of water and the lack of it may well explain its death. Monarda I know nothing about.

The border has been very well prepared, and will be given light organic mulches this autumn and next spring, but I am still a bit concerned as to how plants such as Leucanthemella serotina and Salvia uliginosa, which are supposed to prefer damp soil, will manage in fairly dry, sloping border. Eupatorium purpureum, which I understand also likes some moisture, did not perform well at the top of the border this year - but then it was a young plant growing in a drought, so I guess it might well be fine if we have a more "normal" season next year. (Eupatorium 'Chocolate', planted next to it, has been much happier, and is still flowering now.)

But I am consoled, thank you, that it will not be too late to plant out even small perennials growing in soil-less compost in pots during November.

One more question: I planted some Marguerites this year, both the ordinary white one (presumably Argyranthemum/Chrysanthemum frutescens?) and Argyranthemum 'Sao Vicente' Madeira Series. They have flowered well since the drought. Will they perform again for me next year, or are they best regarded as bedding plants, to be discarded after one season? They came from a supposedly good garden centre (Capital Gardens at Alexander Palace), but nobody there seemed to know.

No, the ground's not dry any more

That was my initial impression after all the recent rain, but after doing a bit of digging, I found it to be barely moist in most places and still very dry under the surface in some areas.

I had a standard Marguerite which was so beautiful, but it did only last the season and from my knowledge of the marguerite it should be classed just as bedding at least here in Yorkshire. It may be different in a warmer south.
Alison

Here is a link that might be useful: Alisons pond and garden

I have a raised box container in a community garden. I planted my Osteospermum early this year and they have done so well that they have taken over more space than I would have liked. They are still in bloom and I wondered if I would damage them if I removed them to a pot.