MNS, there's not a lot you can do to prevent the spume, since it is produced by the nymphs of the spittlebug (AKA leafhopper, froghopper) as they develop. But, since you should always rinse off any leaves or flowers you pick before using, and since the spume does rinse off easily, it should not be a problem to remove it, as disgusting as you may find the substance. At least you can see it. There are a lot of other 'things' on the plants we consume that are not as visible and, thus, not removed. ThatÂs why you should always rinse well before using. narcnh

Lemon Balm (Melissa officinalis) is an ultra hardy perennial and its natural habit is to die to the ground over winter and re-emerge in the spring. Trying to keep it leafy in the winter indoors is likely doomed to failure imo. Indoor winter growth would almost certainly be sickly and unattractive. It needs its winter rest and trying to make is work 12 months of the year will just weaken it. This post was edited by florauk on Sun, Aug 18, 13 at 7:53

Is your mint indoors? It looks a little etiolated as if it is lacking in light. Aphids love a stressed plant in an indoor environment where there are no predators and no adverse weather. If you can get the plants outside I think your mint will be a lot happier. Meantime hold the pot sideways under a running tap and swoosh the foliage with your fingers.

It may grow past the damage. Or it may not. I personally would eat the fruit they produce--others may have a different opinion--but the badly damaged ones may not produce fruit or only produce a small amount, and it may be stunted. The brown spot on the tomato in the first picture looks like damage from rubbing against the cage. Such damage is no big deal unless a mold or something takes the opportunity to start rotting the fruit or it attracts the attention of a pest. EDIT: For future, maybe you can put your plants somewhere else on your property. If not, maybe you can talk to your neighbor and come to some kind of agreement or you can offer to pull his weeds by hand/hire a neighborhood kid to pull his weeds by hand or something, depending on what problem he's trying to solve.