Currant blister aphids

The the new leaves have recently unfurled on a redcurrant I bought over the winter. And the leaves have bright red blisters.

currantblisteraphid_discolouration_s
Discoloured blistering on a young redcurrant leaf

These blisters look like a text book image for currant blister aphids. Sure enough, when I looked at the underside of the leaf, there was a big fat aphid with a brood of babies…

currantblisteraphid_s
Redcurrant leaf with blistering and aphids

These bugs must have come in as eggs on the plant. According to the RHS, the aphids need to move to hedge woundwort (Stachys sylvatica) plants to complete their life cycle: they’re uncommon plants around here, so this could be the end of the road for these aphids, depending how far they can travel. The damage the aphids are doing looks impressive, but is really of no consequence.

Leaf miner damage on lovage

The leaves of these lovage plants are being damaged by the larvae of the celery fly (Euleia heraclei).

1806celeryleafminers 001s
Leaf miner damage on lovage leaves

The celery fly itself is tiny and mainly goes unnoticed, but once the female has laid her eggs into the leaves of your celery, or lovage, or parsnips, or parsley (or quite a few other plants), you’ll certainly notice the damage they do.

The egg is inserted under the skin of the leaf and the grub lives between the two leaf faces, chomping away and destroying the leaf from the inside. This causes the characteristic scorched appearance and blistering.

1806celeryleafminers 002s
The damage is, aptly, called a blotch mine (you can almost make out the grub in this blister)

The grubs will spend two to three weeks inside the leaf, growing bigger and bigger. They will then either pupate within the leaf, or in the ground underneath the plant. A new generation of flies will emerge a few weeks later ready to start the second cycle of infestation.

1806celeryleafminers 005s
One leaf, two lesions – these are still quite fresh and there will be active grubs inside
1806celeryleafminers 007s
…and here’s the grub

The only thing you can really do, on a garden scale, if you are affected by celery flies is to pick off and destroy damaged leaves as you notice them.

 

Heavy rains: cracked apples

It seems to be turning into a tough year for the apples. The spring was damp and windy, meaning pollination, and consequently fruit set, was quite low.The summer has been unusually damp and, up until last week, quite cool. This meant that the apples were growing OK, if a little slowly.

Then last week we had a little of the “heatwave” that was mainly felt in southern England. That was short-lived and followed yesterday by 12 hours of heavy rains – nothing like the short summer showers the gardens had got used to – and only a cool 13C. All that rain was great news for the soft bodied fruits. The raspberries, currants, strawberries and blueberries were all visibly fatter this morning.

It’s not such good news for the apples. They’ve been a little too exuberant in taking up the water and now lots of the developing apples have cracks in them.

0707crackedapple3

Tough, russet skinned apple varieties (like these) are especially prone to cracking
Tough, russet skinned apple varieties (like these) are especially prone to cracking

It’s not the end of the world for the cracked apples. They will mostly keep growing, but the cracks will grow as the apple grows. That means that lots of them will be better suited to cooking or juicing than munching straight from the trees.

Late flowers, fruit and caterpillars

It’s nearly November, but the nasturtiums are still flowering prolifically.

Nasturtium flower
Nasturtium flower

There are even a few caterpillars of the white butterflies still chomping away optimistically on the nasturtium leaves

Large white butterfly caterpillar
Large white butterfly caterpillar

Earlier this year (April) I was given some seeds for Alpine Strawberries and I planted them without much care or expectation. They have thrived under this neglect and have been fruiting since August; perfect timing to complement the end of my main strawberry crop. The fruits aren’t quite as nice as the true wild strawberries (which fruit here in June), but they’re very nice nevertheless.

Alpine strawberry
Alpine strawberry

Another gift that thrives from neglect is a clump of Miscanthus x giganteus I was given years ago. This is the hybrid Miscanthus that is used by farmers as an energy crop, but it works well as a backdrop or screening plant in a garden. It grows from nothing to eight feet tall each year and flowers very late (but not usually this late). The dead stems will usually stand the winter and provide a favourite spot for insects and spiders to shelter in during the colder months.

Miscanthus x giganteus flower
Miscanthus x giganteus flower

I chop the Miscanthus stems down each spring and then use the stems as a handy alternative to bamboo canes for all kinds of things around the garden. To keep the clump under control, I just mow over the spikes of new growth that try to grow where they’re not wanted.

Rusty raspberries

The warm, dry summer we enjoyed this year came to an end when August arrived bringing with it cooler, damper weather*. Funnily enough, damp weather favours the development of rusts on plants as well as on metal, although they’re nothing to do with each other!

Some of the older varieities of raspberry are particularly prone to raspberry rust (Phragmidium rubi-idaei). I have some Glen Ample canes – apparently it is the most common/popular summer fruiting variety in the UK – and they have rust (my Autumn fruiting varieities are, so far, rust-free). I class Glen Ample as an “older” variety, although it has only been on sale since the 1990s, so it’s not really so old.

Tell tale discolouration on the upper side of the raspberry leaf...
Tell tale discolouration on the upper side of the raspberry leaf…
...the different spore types on the underside of the leaf
…the different spore types on the underside of the leaf

Rusts are fascinatingly complex organisms with a vocabulary all of their own. The yellowing on the upperside of the leaf alerts you that something is going on underneath. Sure enough, if you look at the underside of the leaf the rust spores are plain to see. At this time of year there are two colours: the orange ones that will have been spreading the fungi through the summer, and especially since the rain came; and the dark ones which will overwinter ready to start the cycle again next year.

The spores are more clearly seen here
The spores are more clearly seen here

Happily, raspberry rust isn’t much of a problem and is unlikely to affect fruit production. As with most fungal pathogens, thinning the plants out to ensure good air circulation and practising good hygiene in clearing away dead material will help keep infection levels down. But there are plenty more, and worse, diseases that could affect raspberries – rust isn’t really something to worry about.

*In Welsh, July is Gorffennaf – the end of summer:)

Crocus

Finally the sun shone and the crocuses that had been standing sullenly with their petals stubbornly shut opened.  And don’t they look beautiful:)

crocus flower

Spring flowering crocuses need to be planted in autumn or winter to flower the following spring. But if you fancy something a little different, the saffron crocus (Crocus sativus) flowers in late autumn. You can plant them towards the end of this summer and hope for flowers and your own saffron harvest before Christmas. Harvest sounds like a bit of a grand word for such a small thing: each flower has three stigmas – they’re the threadlike part known as the spice saffron – that’s the harvest.

 

John Steinbeck in praise of the art of grafting…

It’s almost time for grafting the fruit trees again. Here’s what John Steinbeck had to say about this skill:

The men who graft the young trees, the little vines, are the cleverest of all, for theirs is a surgeon’s job, as tender and delicate; and these men must have surgeons’ hands and surgeons’ hearts to slit the bark, to place the grafts, to bind the wounds and cover them from the air. These are great men. (John Steinbeck, The Grapes of Wrath, 1939)

It’s more than 75 years since Steinbeck wrote The Grapes of Wrath, but so much of it remains pertinent today.