When I arrived at Common Ground I noted the garlic growing next to the washing station. It was a thick patch of the stuff (with plenty of weeds of course) and no discernible rows or spacing. I found out it was incidental garlic; the result of a very wet June the previous year which made the garlic go mouldy. Faced with this loss Dave decided to till it all in and this season plenty of it popped up again. Unfortunately, garlic rust started appearing and instead of diagnosing the problem and taking action straight away the garlic fell to the bottom of the to do list the fungus continues to spread.
What is garlic rust?
Garlic rust is a fungus. There are at least two varieties that affect garlic from the genus Puccinia (Puccinia allii and Puccinia porri) I’m not sure exactly which type was affecting us but it looks exactly like the picture to the right; picture credit to Garden Betty. It reduces a plant’s ability to photosynthesise, results in smaller bulbs and can eventually kill the plant.
What causes it?
Garlic rust spores are wind-borne and can also overwinter on plant material. The fungus thrives in hot, humid conditions so given that the washing station was draining into the garlic patch which was pretty weedy and the same place garlic grew last year it’s no surprise it popped up.
What to do about it?
While it seems there’s little to do once the fungus has gained a foothold, Miles Smart from Cherry Lane Farm seems to have had success using rotten fish as a preventative measure in the form of a soil and foliar drench.
If only a few signs of rust are evident then removing and burning (not composting) the leaves or whole plants that are affected can help prevent the fungus spreading – keeping any bulbs or scapes for consumption.
Of course the usual good gardening practices will help keep the fungus away:
- Adequate spacing between garlic plants
- Keeping the garlic weeded
- Planting it in a sunny spot
- Rotating crops so alliums aren’t planted in the same place more than once every three or four years
All is not lost…
We harvested the garlic scapes a little early (end of May) and got a good harvest with minimal rust markings. In an effort to protect the rest of our alliums since the rust can spread to anything in that family (leeks, onions, scallions etc) we harvested the garlic a week after the scapes and while there is a huge variety in bulb size (mostly due to the way it grew) it’s still a respectable harvest and means there will be plenty for our CSA boxes. Normally we wouldn’t harvest garlic until July/August but we also needed the space and it does feel good to get the garlic harvest put away.
Also, according to a study by the University of California garlic that has been affected by the fungus can still be used as seed garlic the next year so we can save some and plant again this fall.