Pesticides

Hi, I planted a load of lavender this spring. It was coming on great then was attacked by some sort of insect which systematically chomped through the flower stems. I had no option but to spray, first of all with an organic fruit and veg spray which was effective for about a week then the problem started again. This time I used bug gun for ornamental plants. This was much more effective but has it rendered my crop inedible? How long before I can use the lavender safely for culinary purposes? I have two small children so don't want to put them at any risk.

 

Ornamental sprays are usually not suitable for edibles, I personally wouldn't risk eating anything sprayed with such chemicals. You should be able to find an MSDS sheet on the internet, this will list the contents of the spray and give any warnings.

 

@Moss
This came up on Gardeners Question Time on Sunday. Their answer was to pick them off or to put yellow sticky traps underneath and then "wack" the plant.
http://www.bbc.co.uk/programmes/b07hj8bb
What do you use the lavender for? I have heard of crystallising the flowers and I think I've seen a recipe for Lavender roast lamb.
I agree with burnie regarding using a spray for ornamentals on edible crops.

 

As JWK says, check the directions on the bottle to see if the product is suitable for edible crops.

 

The active ingredient is 0.05g/l acetamiprid. I think in my desperate attempt to save the flower stems I have rendered the plant inedible! I was going to use it for shortbread, ice cream and lavender sugar. Not now. I hope I'll be able to use next year's crop? Does anyone know how long it takes for this insecticide to breakdown?

 

Acetamiprid is rapidly broken down in the soil, it persists for longer in plants as it is a systemic insecticide. It is moderately poisonous to people.
However it is one of the neonicotinoid insecticides and moderately toxic to bees so avoid use on plants in flower.
Next years crop should be edible.

 

Thanks Nigel, that's very helpful. The last thing I wanted to do was kill bees. I sprayed well before flowering infact it is a long way off flowering yet so hopefully the bees won't be badly affected. I'm going to throw this insecticide away.