Has anybody told you granules are better than the liquid to get rid of midge? Merit is available in granules.

Thank you for your suggestion, Dan. At this time my two insect problems are rose midge fly and cabbage moth caterpillars. They both affect the top/tip of new growth only. I direct a fine spray of Bayer Complete Insect Control only on the first 6 inches of new growth. Covering both sides of the leaves has not been necessary, just enough spray to just the drip stage. I do this every 10 days to two weeks. It takes very little spray and very little time to accomplish this.

If I use Merit as a soil fumigant (its the fumes that kill the midge and/or its pupae at soil level...just put your nose down there and smell for yourself). One can also smell the Merit, partidularly on a hot or humid day when one strolls through the roses. If you can smell it, it is poisoning you too, by breathing it in. A merit fumigation also kills earthworms and other beneficials, or poisons those that survive to the point where robins can be found lying dead in the rose garden...poisoned by eating contaminated earthworms and other insects.

Once a stem has buds developed to the size of a thimble for the hybrid tea type flowers, and adjusted smaller for the smaller blooming roses like Marie Pavie, the rose midge fly ignores the stem. I assume a more mature stem is not as 'tender/succulent' for midge maggots to damage, and either the female does not lay eggs on them or the eggs hatch and the maggots die? off.

Cabbage Moth caterpillars also desist damaging the foliage of new growth once buds are well formed, but in fact they never attack the buds in the first place (so far), and only do cosmetic damage to the foliage. They never go after foliage below the top six inches, again perhaps it is too tough for them or contains natural chemicals that repel them somehow.

Aphids and spider mites are easily controlled by washing them off with a direct, but gently water spray, usually repeated only once in a day or two. The spray is directed to the growing tips for aphids and to the underside of the lowest leaves for spider mites. It is remarkable how easy this method is to perform with great success...not using insecticides at all, just water.

Since I live in an old neighborhood in the inner city, there are few lawns of any size, thus my Japanese Beetle problems are very minimal. However my country/suburban friend's roses suffer terribly from late May to early September from Japanese Beetle hordes, due to the expansive lawns the prime feeding ground for Japanese Beetle larvae.

Again, thanks for the suggestion, but if you have an answer to my original question on battery powered sprayers I would surely appreciate your advice.

Back when we sprayed our roses, several things became apparent, some after decisions were made.
On a hill side, a loaded twenty gallon spray cart can drag an adult down hill. Limit the size of the reservoir to what you need and what your topography will allow your arm to pull.

Fewer plastic parts= better.

Many replacement parts are available at Farmer's Co-ops and can be upgrades on plastic.

Can the battery be recharged easily?

Are the wheels/tires the kind that can withstand penetration by rose thorns?

How easy is it to clean out? and how safe? Cleanliness between sprayings makes things much easier.

For your garden, how many gallons does it take for a spraying of the garden as the roses reach full size in late summer or fall?