I would dig it up now and repot, then keep it inside to grow some new roots. I have found it difficult to manage giant Agaves in small pots. It all works out nicely for a while, but eventually becomes very difficult to keep plants healthy. Though admittedly, I am an in-ground gardener and not the most skilled in the container department.

Agaves are susceptible to root rot in damp conditions. I have heard that the UK is damp. :)

I would unpot it, rinse the roots off, let them dry a bit and snip off any clearly rotted ones a couple of centimetres above the rot.
(I have also heard that you use that new-fangled metric measurement, so I will humour you with metric and "ou" spellings)

Then repot it in a really well-draining soil in a wide shallow pot with really large drain holes, place it in the sunniest, hottest place you have, and ignore it for the rest of the winter.

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"2. Leave the Agave to recover and stop all water. Repot him in spring. "

That might also work. Any time your agaves or cactus are damp enough to attrace woodlice, they are staying too wet.

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hints on keeping these things alive in the great soggy beyond ... Plant them in a mix of "cactus mix" and something like coarse sand for best drainage.

Use wide, shallow pots with large drain holes.

Don't put "broken crockery" in the bottom. It doesn't help drainage at all. Just cover the drain holes with something - I use a chunk of window screening.

Let them get TOTALLY dry before watering them, wait another two weeks, then dunk them in a bucket of water until the bubbles stop coming, then let them drain over a sink. Repeat.

Thanks Germanstar and lazy gardens. I am going to bite the bullet and go with option 1 - the soil is now 3-4 years old and the drainage is not as good as it needs to be (hence woodlice!) and I doubt it will dry enough for him to recover on his own. I just hope I don't lose too much blood in the re-potting process :).

Guy

Lazy gardens - I assume you are saying that once repotted in dry cactus mix I shouldn't water it for the rest of the winter?

Thanks

Guy

If you keep the plant inside, you will absolutely need to water, particularly while the plant has a compromised root system. It is however, very important to allow the soil to dry thoroughly between waterings.

Are you in SW or SE England. Many people in the SE grow agaves outside and Agave americana is somewhat tolerant of moisture and cold hardy for southern England. It really wants to be in the ground. People grow it in Louisiana and Houston and they get60" of rain a year. True, they are a tad hotter. If you are going to grow your agave in a pot . Find another type of agave. There are many that are smaller and friendlier to pots. I don't know what your ground is like where you are.I included an article by Paul Spracklin from your side of pond. He is from Eastern England.

I ADORE Agave ovatifolia for bullit proof cold wet tolerances.

I know, this is not good for your plant right now and removing your current problems.. BUT this really reminds me of the Chinese bound foot. It will never be a healthy plant in that pot. You might plant it in a mound of gravel outside.

Here is a link that might be useful: Hardy Agaves

Hi,

having now depotted the aforementioned agave I found the soil to be pretty damp. I have removed as much soil as I could without really breaking up the root ball and removed the pups for repotting.

Should I continue to break up the root ball or will this cause unnecessary stress? The soil is pretty old and it hasn't been drained well for a while so I doubt its very porous anymore.

At the moment I am letting him dry out and his pups will be repotted shortly.

Thanks to everyone that s offered advice this far - repotting a large agave is not for the faint hearted!

Guy

Hi,

I have completely cleaned the soil off. I have trimmed back any rotten roots, however I have found one or two that were rotten to the point of the plant ( I have hacked these back as far as the plant). Is it sufficient to thoroughly dry the root ball and let the plant repair any damage and then re pot or do I have to keep hacking back until I find healthy plant tissue.

Thanks

Guy

To 'speed up' drying of the roots, you could set it on some newspaper, it will suck up quite a bit of water.
Sounds like there were only few rotten roots, so it should be OK. It is also recommended to trim off any seriously damaged roots.
If any of the leaves are soft/squishy, I would prune them off too.
Cinnamon (powder) is sometimes used to dust over cuts - it helps to keep fresh cuts drying.

Cheaper than cinnamon is sulfur powder (flowers of sulfur), available at any compounding pharmacy.