You wouldn't normally prune anything in the middle of winter, the risk of frost damage, poor healing, and then disease is increased. But if you want some winter decorations then go ahead and cut a few stems. Pruning after flowering is the norm for all spring-flowering shrubs, simply because it avoids losing the blooms. If you don't care about the blooms then you can prune before flowering. Pruning after flowering may lose the berries anyway, but you can sometimes prune carefully to leave them. Early pruning is the norm for shrubs with summer flowers or where you are looking for nice foliage, a good hard cop encourages lots of fresh growth and flowers. Late winter and spring, before the main growth flush, is a good time to remove any dead or damaged branches each year, whether you want to remove more or not. Avoid pruning in late summer and autumn in colder areas, you are likely to force some late growth which may be killed in winter.

This is typical behavior for a scaled-up coil. There could be, however, another cause. Do you have a good service company? Oil-fired boilers should be checked and cleaned annually, no question about it. I've only personally dealt with boilers that are, or would be over 50 years old at this point so I have to ask you some questions about how this is set up. Your hot water is supplied by an indirect tank heated by an third zone from the boiler, or is there an another coil in addition to the space heating coil? If the former, you should not have scale build-up on the coil. I an not saying it did not happen. It cold be caused by a leak leading to excessive water turnover in the boiler. That would be hard to miss but most of the damage may have been done before you moved in and then something fixed. If you have one coil and your DHW performance is poor, your space heat may be suffering as well. I don't think that I have to point out that if that is the case, you really need to get this fixed to avoid excessive oil outlays. (If you have one coil supplying hot water and heat with no heat exchanger somewhere, you have some big problems.) If you have an indirect tank, is there a temp gauge on it? What does it run when you are not stressing it as opposed to use? I suppose there could be something wrong with the tank so that you are filling at the top or drawing from the bottom. I don't know how they are built or how they may break. The coils/boilers that I am familiar with are not tricky at all to remove and clean with hydrochloric (muriatic) acid. You kinda hafta know a little about what you are doing so you don't overdo it and dissolve the metal. My parents went through a period between village water supply shift to harder well water from spring source and installation of a water softener to fix that. During that period, the coil was removed by (very good) service people and brought back with the annual service. My dad got tired of being without hot water for a half day and bought a stand-by coil. that they swapped out. He figured that it might wear out and need replacement eventually anyway so he might as well buy one "now" and have the convenience. Ah, I see now that you probably don't have an indirect since you wrote about that option in the future. I missed that.. Are you thinking about an electric "tankless" I don't think that is going to be your best option. If you have hard water, don't do it. it will be a more difficult task than keeping the boiler coil clear. Even if you don't have hard water, I don't think it is your best option. Are fuel oil , propane and electricity your only options? Just crunch the numbers to see which gives you the best outcome. If it is electricity, get an electric tank or figure out if a heat pump water heater makes sense. (If electricity is less expensive, it will be to heat the house as well so you might want to get an electric boiler if you like the HW baseboard.) If fuel oil is a less expensive source, and you have hard water, get the coil cleaned and install an indirect tank if you want a permanent fix. (Either that or install a water softener. My parents never regretted their decision. you might need to clean the coil every few years, but it will not be nearly as often.) You know, if you are in a temperate climate, and this is a hot-start boiler that makes your basement too warm in the summer, you might be better off turning it off and running an electric (HPWH?) tank in the summer. That is especially truer if the basement is humid. Go back to making hot water with the boiler in the winter if the investment in an indirect tank is not too much to recoup. The boiler is idle most of the time under those conditions and it costs a lot to keep it warm. You could consider having your plumber install a flat plate heat exchanger to heat water in your electric tank so you don't have to invest in the indirect and have that take up space in addition to that water heater..

"What is the down side of leaving the plant where it is?" Right now it is tight against the fence. There really isn't room for it to get any larger without it losing that nice shape. In general garden beds look much better if they aren't so narrow because it allows arrangements of plants in some form other than a straight line and plants can grow to their natural proportions. The current spot may stain the fence with mildew since it won't dry quickly with the plant's foliage releasing moisture via stoma (pores) and also holding moisture from rain. I try to make my garden beds a minimum of 5' deep front to back (depending on what I am planting in it) so I have a foot between the fence and the back of the full grown plants and in some spots have room for two or more layers of plants front to back. Many of my garden beds are deeper than that. Did the plant bloom for you last year? If the flowers were blue or purple, it is a big leaf hydrangea, Hydrangea macrophylla, and will do best with no pruning of live branches as GG48 said since you might cut off the flower buds. If blooms were white or pink, you will have to wait until you have a better photo.

You can. The only thing I would watch is moisture getting in the fresh cuts. You can use wood glue or even crazy glue to seal the cuts but if I were to repot and prune at the same time I would leave them inside for a couple weeks or more. And just moisten the top of the soil. Dont do any deep watering till you see some new growth. Just my opinion but I have not lost one yet. I shouldnt have said that but I have had a couple of mine for almost 22 years now. I've seen people pull the plant and heavily trim roots and scoop out root rot then leave the plant in the sun for a month (not in any substrate) before planting back in soil and prune them, and even cut the leaves, and they are fine. Other than root rot from too much water these plants can take ALOT of stuff (for lack of a better word)