Garlic Rust has been devastating to many experienced hard core garlic growers. Here at Koanga we lost our crops seriously the first year it hit, but we couldn’t just throw it out and buy more garlic, our cultivars were not replaceable.
If all the things I have been learning and teaching over the past 10 or so years were true then we should be able to sort the garlic rust.
My understanding from all I have learned studying Dr Carey Reams Book Nourishment Home Grown and working with Grant at EF etc, tells me that if the garlic has rust or any other disease it is a result of mineral imbalance or deficiency.
So.. the first step is to do a soil test. If you are growing large areas of garlic for sale this is not a significant cost. We did that, and it was very clear that we had planted our garlic into beds that had very low calcium /magnesium ratios as well as low levels of calcium. We had been doing our soil tests after the garlic went in, ready for most other Spring crops, but this experienced changed when we take our soil tests from then on. Calcium is responsible for cell wall strength, and disease resistance.
We worked on improving the available calcium/ magnesium ratios and levels for the second year but we still did not get them high enough or balanced enough. We still had rust but not as bad as the first year. (We used EF:Nano Cal, as our calcium was way too low compared to magnesium. If the magnesium had been too low we would have used EF:Soil Mag)
Some of our seed garlic went to Peter Alexander that year and he grew it in his amazing Hawkes Bay, Norton Road, fertile soils and it grew to be huge. The problem is clearly not genetic. Ours was not as big as previously, but better than the disastrous previous year.
Each year we have totally focused on ways to get the available calcium/ magnesium ratios balanced and levels high and each year the crops have got better.
Some people say that planting further apart helps, my understanding is that if the nutrient levels are too low then that may help, but we need economic returns for our work so the only solution is to get the available mineral levels balanced and high. This is year 4 since the bad year, each year they are getting bigger and healthier again.
One of my research projects this season is to see if we can supply the minerals using buried decomposing ramial wood chip.. buried in the garlic and onion beds down to 5cm the previous Autumn and planted in lupins, then the lupins are taken out in August and replanted with the main crop garlic and shallots and onions.
I did that in my garlic /onion bed last Autumn, and right now that bed is full of white fungal hyphae, decomposing the ramial wood chip, so I’ll let you know how the garlic grow this year.
Kay Baxter, July 2019