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Hi,

My cabbages and cauliflowers were all growing well, but I have noticed that one of the three cabbages has stopped growing and the leaves are turning pink/purple. I think this might be clubroot but I'm not sure. Would value the opinions of more experienced veg growers. Hopefully there should be a picture attached! It's not brilliant but it does show the cabbage on the right is not growing as well as the other two.

If it is clubroot, should I dig out the affected cabbage or would that put the others at risk more (I've read it is very easy to spread)?

Clareg

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hi Clareg,
First thing you need to do is establish if it's clubroot or not. The symptoms you describe (stunted growth, discoloured leaves) could also be Cabbage RootFly infection (CRF). I would dig up the "infected" plant in your pic (taking care to take up the entire root for inspection) and check the roots for the classic clubroot galls (a bit like root ginger but not as large). If the roots look black and rotten, then you have CRF.

I do hope it's CRF (in a nice way of course!) Clubroot is a real headache for anyone growing brassicas. About impossible for the amateur gardener to get rid of it without using the chemicals the professional growers have access to.

Let me know what you find and then we can offer some advice based on the results,

Regards

Forgot to say earlier that it could be a nutrient deficiency, the stunted growth and purple tint on the leaves sounds like phosphorus deficiency.

See what the roots tell you

Do as jondanie says and have a look at the root. The cabbage is US now, so you have nothing to loose.
If the roots are like a swollen hand its clubroot, although usually all would be affected.
It's more likely to be cabbage root fly and if it is there will be one or more small maggots in the roots.
Stick collars around the rest to stop them being attacked!

__________________
My Majesty made for him a garden anew in order
to present to him vegetables and all beautiful flowers.- Offerings of Thutmose III to Amon-Ra (1500 BCE)

Hi,

Thanks for your suggestions, I'm off to the allotment tomorrow (taking advantage of a few hours off work to go to the dentist!) so I will dig it out carefully. I'll take some pictures and post them.

Clareg

Good!
Looking forward to the pics

Hi,

Well I've been back to the allotment and dug up the affected cabbage. In fact, it didn't need digging up it came out really easily. Very little root on it. I managed to take some pictures with my mobile phone so sorry they are not good quality. Although the root is stunted I spotted 2 little white bugs, one looked like a tiny centipede while the other was half buried in the root so was difficult to see, looked like a little maggot.

Does this sound like cabbage root fly? I've spotted two of my cauliflowers that now have purple tinged leaves too, so looks like whatever the problem is, it is spreading.

I have what I thought were cabbage collars around them, but I've realised they are strawberry collars instead (doh) so I will need to buy the real thing!

I'm just about to go on my hols too

Clareg

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Hi Clareg,
Thanks for the pics, from your description of finding small white maggots and the root destruction, i would say it's cabbage root fly. The first hatch in May is always the most destructive.

The situation is not good for your remaining plants. You may lose them too. Any infected plants and maggots that you can find should be destroyed. Any maggots left behind will form a pupa which will remain in the soil to emerge next spring. Snadgers tip for using the collars around the plants will help at initial planting, the collars you used mightn't have given a 100% protection.

I don't know if you can get a few more plants from somewhere and plant them in another area of your allotment. Maybe not worth the effort now.

Hope this helps,

If you need some more plants....

I have noticed more garden centres (in my area anyway) have a vegetable section, with packs of 6 or 8 seedlings in.

If your crop is ruined, it migth be worth buying some in and planting them elsewhere, just so you don't lose out on the produce?

__________________
"Its not who you are underneath, it's what you do that defines you" - Bruce Wayne

good idea,
Worth a try. Just need to prepare for the next hatch at the end of June using the collars as already mentioned and planting in a different location.

Cheers everyone, I still have some cauliflowers growing in the greenhouse (as a "just in case"!). I haven't seeded my savoy cabbage yet so they could replace the infected cabbage.

My bed is divided into 3 smaller beds and so far only 1 is affected. The middle bed has nothing in it and the end bed has brussels sprouts which are currently covered. If I'm lucky, it will just be this first bed that is infected.

I'm going to see whats open tonight to see if I can buy the cabbage collars before I go on my hols tomorrow, otherwise I will have lost everything by the time I get back.

Thanks for all your help, what would I do without this forum!

Clareg

You can make collars from a piece of cardboard or similar just cut a slit from the edge to the middle and then cut out a cross in the middle.

Thanks for the tip TEB, now then, there's no one else in the office at the moment....

You're welcome,
no need to spend money on collars, do as TEB has said.

Carpet underlay or thin roofing felt are also good collar making material!

__________________
My Majesty made for him a garden anew in order
to present to him vegetables and all beautiful flowers.- Offerings of Thutmose III to Amon-Ra (1500 BCE)

Not too eco and all that but you could try sterilising the affected bed with Jeyes if you have lost all the brassicas in there. Also have a look at some of the root dip treatments at the garden centre - there may be something there that might help?

Terry

Terry,
I'm pretty sure Jeyes or any other strong disinfectant wouldn't be much use against insect pests. Jeyes is useful against Clubroot.

Good idea of having a look in the garden centre for a root dip, I thought there was one available but probably not economical just for a few plants.

Re clubroot...........stick a bit of rhubarb leaf in the planting hole! Its active ingredient is oxalic acid and it is supposed to deter clubroot.

__________________
My Majesty made for him a garden anew in order
to present to him vegetables and all beautiful flowers.- Offerings of Thutmose III to Amon-Ra (1500 BCE)

Hi,

So I managed to make cabbage collars from cardboard and put them around the Brussels sprouts in another bed. I have dug up the infected plants and placed them in a bucket for now (how does everyone else dispose of infected plants?). I decided to leave the others and see what they are like when I come back from my hols, as visibly, they look unaffected. If I've lost them all, I will not use that bed again this year. If I sieved the soil could I get rid of any maggots that might still be lurking?


Clareg

Generally I either burn infected garden waste or black sack it and take it to the dump - just remember it can't go in 'green waste' as thar would defeat the purpose!

Clareg,
Burn or bin the infected plants.

Once the maggots mature, they leave the roots and pupate into a pupa.
Sieving the soil within 6-12" of the root zone should get most of the maggots, You'll need to also look for any pupae (reddish brown colour) that have already formed. A lot of these will hatch again around early July so the infection starts all over again.

It's probably too much hassle to sieve the soil, best to protect what you have already with your collars. Maybe investing in a crop fleece would be a good idea too, since you don't have too many to protect

Snadger,
Yeah, old trick of using rhubarb leaves or stems for clubroot control. Never used it myself, jury seems to be out on whether it works or not! Some people swears by it though.

I once new a guy who wore a copper rumation bangle to ward off arthritis when asked whether it worked or not he said " Well I've got no arthritis!"

I used rhubarb leaf last year on clubroot infected land and got no clubroot problems. The problem is I didn't do a control in that area without rhubarb, so as you say, the jury is out!

I have now moved plots and hopefully left the clubroot behind!

__________________
My Majesty made for him a garden anew in order
to present to him vegetables and all beautiful flowers.- Offerings of Thutmose III to Amon-Ra (1500 BCE)