[Josh Willis]

As a grower once burned twice shy of spraying during bloom (bad Neem math and drift to our Pears), I thought it’d be wise to ask other growers rather than just trust the label. Does anybody apply Silica, in particular via SilMatrix, during your bloom?

It would seem to make sense as a fortification during this very sensitive growth period. But I’m not going to pretend to know the details.

I noticed Michael didn’t list any Silica addition until the comprehensive sprays. Obviously it is great for that early developing fruitlet. But I would think it might be helpful for those early bud leaves, too, especially to protect during some of the initial ascospore releases and prevent primary infection. I want to say Brittany mentioned spraying Sil-Matrix from green tip to a few weeks after petal fall for that very reason, but I can’t find that forum thread, so this might be my imagination.

[Chris McGuire]

We sprayed 0.5% Sil-Matrix in the middle of apple bloom last year, together with sulfur and potassium bicarbonate. Did not see any noticeable ill effects.
Chris

[Dan Lefever]

Have used SilMatrix prior, during and after bloom. this to strengthen and build cell walls against disease invasion. Have used along with Ca and boron sprays to limit or eliminate fireblight nutritionally. do not mix it with any other mineral based spray materials particularly humates; as it will precipitate the potassium silicate. other sources of Si that are less or not vulnerable to precipitation: Tera Vita SP85 or 90 water soluble humic acid (from Organic Approach) is 7% available Si, Horsetail tea, EckoSil Shield from Sym-Agro.com
listen to Graeme Saites Nutrition farming podcasts, had one about three years ago specifically on Si nutrition and disease control.