Wilt in the heat
As I write this it is raining! In fact the county is under a yellow rain warning. I have never been so pleased to see the rain. As long as it knows when to stop. But it can rain all it likes for a few days because it will take a lot of rain before it does much good and soaks into the ground and revives flagging plants. But it won’t save my asters!
This summer has revealed a new disease to add to my long list of fungal infections! .Last year it was the cosmos that succumbed to cosmos smut. I was so disgusted that I decided that I would not grow any cosmos this year. It was as though I was betrayed in the most terrible way by an old friend and I could not forgive them – in reality I am more forgiving but not with the cosmos.
This year I decided to grow Chinese asters (callistephus) for cut flowers for the stall. I have grown them in this garden before but only dotted them about the place to be raided, when necessary for cut flowers. I have always grown the single ‘Madelaine’ types but this year I decided to grow some relatively expensive, single-coloured, doubles, one in lilac and one in purple. I have picked a few to mix with orange rudbeckias to make up ‘Wexford bunches’ – purple and gold are Wexford colours – and they have sold, though I can’t beat pink bunches which always sell best!
No sooner had the plants established and started to make headway than a few plants collapsed. Not many each week but a few at a time. Oddly it was the double row of lilac that went first and I dug up the plants and it was almost certainly leatherjackets or cutworms as the stems were eaten through at the base. But in the last few weeks many more have been dying. This cut flower bed is watered every other day and I direct water at the roots and give a good soak to keep all the plants growing.
Everything else is fine and the double row between the rudbeckias and carnations are all good at the moment. But the other rows are dropping like flies and I fear I have ‘aster wilt’. This is a form of fusarium fungus, a soil-born disease that affects a wide range of plants but this one has its own name – Fusarium oxysporum callistephi. I cannot be absolutely certain it is the cause of the plants’ death but when I pull them up they have a good root system, ruling out soil pests, but black roots and stem bases. It is said to affect plants most in warm weather and just before flowering time so it seems likely.
Where did it come from? I have not grown asters in this bed before. If I grow asters again it can’t be in this bed. Fortunately I do have several beds so I can, and do, shuffle things around and next year I will have to plant the beans and courgettes in here and put the asters elsewhere.
Fortunately, at present, I have plenty of asters to pick for this weekend which is the local ‘pattern’ or ‘cemetery day’.
The Biking Gardener 
Oh, there seems to always be problems in a garden. We also had rain but not the forecast downpours and really need a lot more rain to restore moisture levels in the garden.
Yes we had about 6mm but it was not enough to reach areas under hedges where the soil is still dry. But it was welcome.