Sedum Stonecrop Autumn Joy, what is eating my plant?

I have in several places in the garden Sedum Stonecrop "Autumn Joy". The last couple of years the flowers are being attacked by I think some form of a slug/insect. The leaves curl up and collapse and the flower dies.Yesterday I found a very tiny brown slug about 4-5mm on one. Any tips what the problem is and if there is anything I can do that is organic. At the moment I am cutting away the part that is affected.

 

Looks like a bit of slug damage but the curling is probably down to black fly, aphids.

 

Thanks that was quick! I appear perhaps to have two problems then. Any tips what I can do? Is there an organic spray I can make up perhaps against the aphids? I have so many plants and of course it is a shame to have no flowers for the Autumn.

 

I don't know what pest is attacking your sedum. I don't know if sedum is ok with it, you could try this on a tiny area first, but SB plant invigorator is quite good for aphids and as far as I have read doesn't harm ladybirds, green lacewings, hoverflies or bees. I personally wouldn't take the risk of spraying it directly at beneficial insects though. It is a bit secretive about its ingredients, but it seems to be some kind of horticultural soap with foliar iron and probably a few other things. I used too much on sensitive plants and got brown bits, though big roses were fine and didn't get any brown bits, they seemed to thrive on it and turned greener and healthier, probably from the iron foliar spray. Sedum is I think a rock plant that might prefer alkaline soil, so I don't know how it would react to iron, but I don't know and have never grown sedum. I think I might have overdone its use in spring before the predators got going. It is cheapest to buy it as a concentrate that you dilute and put in a spray bottle.

Now it is summer, if it was me I would get some green lacewing larvae. They are great fun, amazing little creatures that totally clean up greenfly off plants that were infested. They eat various other pests as well. Then they turn into beautiful lacewings and if you are lucky, and don't have ant infestation, you get a few of their lifecycles. They need a fairly warm outside temperature, so you can only use them once summer gets going, not early spring.

I am currently at war with some ants putting blackfly on my nasturtiums and a few other adjacent things they decide to try. I have been spraying them a bit now and again with SB plant invigorator, and it seems to annoy the ants, and the blackfly look desiccated. It doesn't kill the ants, but they are affected by it, they are intelligent creatures and they might be getting the message to go somewhere else.

Blackfly are horrible, greenfly too, and they seem to attract a fungus or something that destroys plants. They are herded by ants for their sweet honeydew, and ants attack green lacewings and ladybirds at some stage in their lifecycles, and probably other aphid predators too. Blackfly are usually associated with ants.

If it is slugs attacking your sedum, you could try the "organic", and only legal form of slug pellets, made of iron phosphate. It doesn't harm bees, pets or children, and disintegrates in the soil into iron and phosphate that plants can use as food. You can get these for one pound from Poundland. If you want to try something more expensive, there is Nemaslug, made with nematodes. I have never tried it, and when I recently looked all the suppliers have sold out. It says it is mainly for slugs, not snails.

 

Thank you for all your tips. I seem to at last to be rid of the problem for the time being. The stonecrop looks much tidier now since I cut of all the curled/dead bits. Side shoots seem to be developing so perhaps I will have some sort of a flower for the Autumn I will be armed with a spray next time it happens!!