Insecticide for lettuce?

I've noticed an increasing number of aphids on some of my lettuce (not a problem I've ever had before) - I've 'blasted' them with the hose but many of the little blighters are still hanging on and whilst they don't appear to be doing any significant damage, they are (as my daughters would say) 'gross' to look at.

The next step is a soap spray but I'm not sure how much soap to dilute into a 1 litre bottle - does 20 ml sound about right?

 

You want to eat soapy lettuce?

 

I use one teaspoon (which I think is 10ml ??) of Horticultural liquid soap per Litre of water when making a spray for Aphids etc, and I put two teaspoons of Neem oil in with it. I apply in the evening and then wash the leaves off the following morning (some plants are more effected than others). Non Horticultural soap may effect the leaves more (I forget the chemistry, but Horticultural soap and Detergent like washing up liquid start from different chemicals, Phosphorous springs to mind, but I can't even remember which of the two that is!!)

 

One teaspoon = 5 ml. One tablespoon = 15 ml.

I'm about to mix some neem solution and will try Ecover washing liquid for fine fabrics and wool as the wetting agent. It's supposed to be rapidly bio-degradable and doesn't have any phosphates added.

Got quite a lot of RSM on our potted peach and on one cuc and regular spraying with SB Plant Invigorator doesn't seem to doing a lot of good

 

Not the least bit scientific, but:

I had RSM on my cucumber plants, and severe infestation of aphids on my Aubergines (I've never known aphids that early in the year). I crushed the aphids between thumb and forefinger daily, but it didn't really seem to make much difference to their numbers.

I mixed horticultural soap and Neem and sprayed to completely wet top and bottom surfaces of the plants. They where in 4" ~ 5" pots, so it was easy to pick them up and angle them to spray effectively.

I did this in the evening, and then washed the soap off the following morning before the sun came on the plants and scorched them.

I repeated after 2 days.

I haven't seen any RSM since, and have had just a few aphids - which I have been repeat-spraying with Soap/Neem about once a week - when I notice a few critters.

The older leaves of cucumbers and melons went crispy like like paper. Hard to say if that was the RSM damage, or reaction to the Soap/Neem. Whilst waiting for those materials to arrive I sprayed the Cucumber/Melons with spray made from Fairly Liquid detergent, so that may have upset the leaves.

If this is representative of how it is likely to work in the future that I'm converted!

 

.

I only grow Iceberg types of lettuce which have tightly packed leaves and because of aphids getting into the centre parts and also the rain rotting the central leaves, I started growing them under cloches.

Once they have started to heart up, it is no use spraying as the spray never gets near them.

I do not have almost any problem with either now.

Ps. I buy the corrugated plastic sheets ( 72 by 30 inches) for the cloches from Wickes, where else, who are by far the cheapest!

 

Greenfly seem to be exploding this year!! I went out and collected abought 200 ladybird larvea and released them into the polytunnel, they munched their way through a lot but now most have pupeated and I'm waiting for the adults to emerge and restart the cycle. Aphids seem to be winning though.

 

I would prefer ladybirds to soapy lettuce
I just don't fancy eating anything that has been sprayed with soap :(