aphid attack

My Veitch blue had a bad aphid attack. I sprayed it with a off the shelf bug spray used on practically my whole garden. It is the first year we have had this plant. The bottom leaves have now turned brown and dry there also seems to be a white thread like a spiders web between the leaves and the stem also a white salt like crystal has formed in places. Is this damage from the spray? it hasn't done it on anything else and was a leading brand or do i have another nasty bug?

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Re: aphid attack

Reply from Kathy C

Hi, Aileen,
Could be spray residue. Next time purchase an insecticidal soap applied after you have sprayed as many aphids off with the hosepipe as you can (without damaging the plant). Or, make your own spray with crushed garlic and washing up liquid added to water. You will need to spray every 3 days or so because those pesky aphids will keep coming back.
Kathy C