Live webchat with gardening expert Phil McCann, today, 1-2pm

Hello Phil,

I'd love to know if it is really possible to eradicate Japanese Knotweed from a garden. We've reduced it drastically in ours over the last five years (it had been left for over twenty years and had spread over a large area) but small shoots keep reappearing and we keep respraying with RoundUp. It never gets higher than about 40cm now whereas it was about 2 metres high when we first came. Are we doing the right thing? Will it eventually die? I had hoped to have a vegetable garden but of course I can't disturb the ground until I know the roots are dead.

Do you know how the experiment with the J.knotweed-controlling insect is coming along?

I can see that in the future there is going to be more and more need of water conservation with climate warming and the cost of water escalating.We should start now with getting into good habits and watering at the right time when the plants need it, not too early and not after they have wilted.What is your best advice to pick this up? or is it just experience. Are there any other conservation suggestions you can make that can be used on the alloment and that will not cost an arm and a leg

I live in Aberdeenshire and winters can be very cold. I have a polytunnel for the first time this year. I have grown a lot of perrenial flower plants from seed. A lot of them too small to plant out as it was quite late in the season before the tunnel was up and running.
What should I do to ensure that they survive the winter given that last year we were down to -20c at times?

Hello Phil, I have a hardy banana (Musa Basjoo) which is at present in a tub. It has however got too big to move, so must be planted permanently in the garden next spring. How should I over winter it in future, do I cut the leaves off before wrapping it up etc. I live in North East Essex.

Hi, I wonder if you can give me some guidance on walnuts. My daughter has just acquired three flourishing trees but we're all at a loss as to know when is the optimum time to pick and how do we know from the outside if they are ready to eat? Some are very light and I wonder if there is anything inside them at all. We were also warned that if we don't get there in time the squirrels will. Would appreciate your advice as there is such a bumper crop.

Hi Phil - I'm new to Gransnet and this is a great opportunity to get some good gardening advice. I've recently moved to a house with a space called a garden that in fact was once an outdoor museum: the ground is compacted by vehicles and people that used to drive and walk over it and there are also areas of rubble and broken concrete, so you see that I've got my work cut out for the next few years! When we moved in some bamboo planted along a wall was 20ft high and I have repeatedly poisoned it with Roundup tree stump liquid, but it's still coming back. Even the parts that seem to have died off have enormous root systems. Please, please can you suggest ways of finally getting rid of it so that the land can be cleard for something less invasive!

We have a wonderful gunnera and want to prepare it for the winter. What do I do with the seed pods when I cut the leaves and put them on the heart for protection?

I have had a Blueberry for 4 years now and it is in good shape.
Do I need to prune it at all.
I know how to prune most of my fruit bushes and trees, but
Blueberry is new to me. Many thanks for a reply.

I have a 10 year old Robinia and a philadelphus. Both have never been pruned and are spindly and bare at the bottom.
The philadephus has very few flowers and the leaves on the Roninia are quite small and not very red.
Should I prune these and when? bearing in mind that I live in Aberdeenshire and winters are very cold.
Would feeding them help?

Hello Phil,

I won't be able to "watch" as I will be at work, but I would very much appreciate your advice re my cordyline.

Like many, it suffered badly through last winters snow, and we actually thought it was dead. We were advised to cut it down drastically, which we did. It has now sprouted lots of "baby" plants, not from the stem but coming up through the compost (it is in a very large pot).

Can I take some of these and pot them up to grow on, and give some to others, and if so how should I do it?

I did "lift" a couple earlier in the summer and pot them up, but they didn't seem to have any roots and just died.

I now have a pot with the stem of the old plant, and lots of new plants around it, what should I do?

Thanks in advance!

Phil, I have had loads of strawberries in my raised 1 metre square bed this year and plan to move a few plants shortly, to another raised bed. I have been plagued by small slugs, which have eaten chunks out of the strawberries so a lot of been wasted. Can you advise how much I can wash off and clip away from the plants to avoid taking slugs and their eggs into the new bed, please? And is there any particular raised bed that will make it less likely for slugs to get in there? (I have seen some beehive shaped ones that look good, but don't want to spend over £100 to find the slugs are still enjoying my strawberies). Thank you.

I grew a good crop of tomatoes this year in a container, but they had tough skins and tasted a bit bland. I could buy better ones in the farmers' market. What is the best variety to combine decent cropping with good flavour which you can grow in a container?

Thanks!

I have an indoor chilli plant which has produced lots of chillies this year. However, it has slowed down in the past two months and the chillies haven't matured. There are also tiny flies which sometimes appear when the plant is touched. Do I have a pest problem and is it the slow season now? Your advice would be appreciated. Many thanks.

Our small front garden wall has been damaged by the roots of cherry trees. What quick growing plant can I buy that will cover it and disguise the damage?

I don't really have any 'light in a window' space for me to grow indoor plants, though I'd really like to. Are there any that can either live outside during the cold winter or can deal with not having any light? I like the idea of chillies, as above, but not if this really is the slow season as ameliaanne suggested.
Thanks Phil

Hi Phil, welcome to Gransnet. I have a garden with a lot of Mediterranean-type plants - thyme, santolina, lavenders, hebes, myrtle, with more perennials for temporary colour. The only trouble is that after July there's not much colour apart from a few bits of verbena bonariensis. Can you suggest any plants that would go with the above and provide (preferably long-lasting) colour through August and September?

I had three arbutus trees in large pots against a wall but they have succumbed to disease. I don't know if this was the way I kept them; I was told that lots of arbutus trees had died in Britain. Anyway, I am looking for something of similar size that would give an architectural shape against a grey wall but that isn't a succulent or too exotic-looking. Any suggestions?!

Can you suggest some plants for spring colour and preferably scent in a North-facing, slightly damp area of garden underneath some acers? Thanks!

I grow tomatoes, lettuces of various kinds and runner beans in pots - all very successfully until the slugs get them, when I am left with shredded leaves, slimy trails and, this year, not a single bean. I don't really want netting etc because these pots are partly ornamental. Is there any slug/snail preparation I can use that is safe for human health? I wash the veg, obviously, but it still makes me uncomfortable putting chemicals on it. If I use the blue pellets I see them on the earth and they make me feel slightly sick - I don't much fancy eating my produce afterwards.