im a keen gardener i grow spuds, toms,carrots, black currents, apples, rocket, basil most herbs, most lillys, tulips and loads more, i dont use any pesticides the only chemical i use is for the compost heap to rot it down quickly, do get rid of carrot fly i plant them in high containers as carrot fly's only hover no higher than a foot. to get rid of scarlet beetles of my lillys i either flick them of or i use lady birds but when they are at larvey stage. i have some 30 huge conifers in my back garden so i always have lots of birds and spiders i did how ever have a huge bee and wasp problem last year the bees didnt bother me as they where hunny bees so there not to much of a problem,but the wasps where so big they mad a nest in the shed so i had to call someone out to remove it which cost a pretty penny.
i do have a huge problem with ants in the summer and i do treat these as they come in the house (red ants) god they hurt when they bite. i dont spray or use powder i use ant bate stations its a plastic pot with gel inside this attact the ants they take the gel back to the queen and with in a week your problem has gone.