I had initially used Pro-Tekt silicon solution for hardening off green growth for winter after hearing about it on the forums. But last year I tried it for fig rust on problem trees, and the result was amazing. It stopped the fig rust - and it also stopped fig splitting. http://figs4funforum.websitetoolbox.com/post/splitting-and-fig-rust-symptoms-of-nutrient-deficiency-8471398?pid=1295387323
I decided to use it on all my figs this year, and have made four applications, starting as the fig buds were beginning to form on the new branches. On susceptible varieties, leaves that formed before the applications started, showed rust symptoms, but those forming later do not.
This is Wuhan:
As the figs continued to form, I noticed something else – I wasn’t seeing insect damage! Every year the figs – especially “hairy” ones like Celeste, Florea, Hardy Chicago, etc. – have been attacked by thrips. (http://www.tswvramp.org/vectors/index.html See thrips damage on tomatoes towards bottom of link.) It was early in the fig formation, and I thought it might just be wishful thinking on my part. Figs are ripening now, and the figs are still unmarked. This is what the initial thrips damage looks like:
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After the sap dries, a brown scar forms.
I’m still seeing sap droplets, but they are much smaller – and the brown scars do not form.
These small drops are what I’m seeing now.
I’m assuming that the insect is able to pierce the fig and make a hole - but unable to inject saliva – which is probably what causes the brown scarring.
When I had first posted about silicon on the forums, some folks who used organic methods felt that natural compost materials would provide all necessary nutrients. I don’t disagree, but I question how much silicon would be available to the fig tree – or how quickly. The Pro-Tekt is very fast. Joe Dewhirst found this list of silicon containing plants for those who prefer going the natural route. It identifies plants with high silicon that would increase the silicon content if incorporated in compost. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4247092/table/TBL1/ One plant that is attractive, easy to grow almost anywhere, and can be cut regularly is Phalaris arundinacea – Ribbon Grass. Just be aware it is invasive.
This is the article that contains the table: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4247092/
I’ve been trying to fine tune application rate and timing of the Pro-Tekt. To harden my trees off in the fall, I used 8 oz. in 5 gallons of water which is further diluted by a fertilizer injector set at 1:100. A tiny amount – 1 cup in 500 gallons (roughly 1 teaspoon in 10 gallons). At that rate, I water till it runs out of the pot once or twice a week without any problems.
Last year for the fig rust susceptible varieties, I used a watering can with 1 teaspoon Pro-Tekt in 2 1/2 gallons of water in three separate applications one month apart. I didn’t water as heavily as previously. I didn’t see any problems with the trees with either regimen.
This year I increased the Pro-Tekt to 2 cups in 500 gallons once a week, watering until it ran through the pots. After the fourth application, I noticed leaf curling on some varieties. The Fico Gentile leaves were the worst. The newer leaves pointed up and curled.
Other varieties showed a little twisting, but others, none. You can see that the leaves on the plants behind the Fico Gentile look normal. I think the combination of a higher concentration, too frequent weekly treatments, soft, lush leaves, and variety susceptibility to silicon caused the problem. The plants and figs are fine - the problem just seems cosmetic. Next year, I’ll stick with the 1 cup/500 gal./once a week (or less) protocol. This year, I’ll be treating again next week. This is my usual start time for hardening off soft growth for winter.
Once the silicon is deposited in the plant it doesn’t move, so it seems reasonable that silicon should be made available during growth (leaves and fruit) to maintain protection. I’d appreciate hearing about others’ experience with silicon applications. This is all new, and I’m just working by trial and error with application rates and frequency. But one teaspoon per 10 gallons seems to be well tolerated on a weekly basis.
The Pro-Tekt has been a game changer. It protects against insect attacks and fig rust – fairly minor, annoying problems in New England. But to me the biggest impact is with splitting. Usually, I’d pick anything even close to ripe before rain. Otherwise It would split and have to be discarded. Now, I just leave the figs on and wait until they ripen after the rain. That’s big.
This probably sounds too good to be true – a nutrient that solves insect, fungus and splitting problems. I know it has me stunned. When I first mentioned my experiences with silicon, I thought it was some obscure little nutrient. But apparently, it’s the “hot new thing”. It’s being used to treat many edible crops. Even my bags of Sungro potting mix contain it. The academics doing research don’t know how this stuff works – but it really does!