My greenhouse is kept at 60F lows in the winter, rarely goes much above that during the day, and although my species and hybrid Phals do alright at that temp, they don't really like it. Most Phals prefer warm to hot temperatures and do best in the 70-90F range. But they make it through my 60F winter nights, although the spikes on the hybrids usually are delayed as they slow down and even stop growing until the temps get warmer. The species Phals usually bloom in the summer and don't spike during the coldest months anyhow so that is not an issue. My suggestion to you is to keep them as warm as you can. 50F is definitely too low, even 60F is a bit low to keep them completely happy. But put them in the warmest location you have in the house and let it go from there. They should do okay and grow for you. (Don't go by the house thermostat but rather check the high and low temps exactly where the plants are) Arthur, I leave my lindenii (and wilsonii) outdoors all winter down to just a tad above freezing, and keep them in the air-conditioned house during the summer heat. These are cool-growers and will croak if kept with other Phal species and hybrids in warm temps.

All azaleas tend to loose their leaves. Deciduous azaleas loose their leaves every fall and get new ones around May some time. Evergreen azaleas have dimorphic leaves, known as spring and summer leaves. The spring leaves unfold at the beginning of the growing season and are dropped in autumn. Summer leaves emerge in early summer and are smaller, thicker, darker, and more leathery than spring leaves. They remain on the plant during the dormant period and drop in the spring, however, summer leaves may persist for several years in warm climates. Some "evergreen" azaleas are deciduous in colder climates. Sometimes this is called being semievergreen. Wait until mid May for signs of life. It is good that they don't break dormancy before our last chance of frost.

Deciduous azaleas are very hard to root. I would have a professional do it. You might contact Kathy Van Veen in Portland, Oregon. She has a service to root most rhododendrons and azaleas. The one branch per year is a very arbitrary. A rule of thumb is to not remove more than 1/3 of the leaves in any season's pruning. Most azaleas will take more pruning. There are several fungi that are common on azaleas: Sooty mold growth on stems and petioles is a symptom of Azalea Bark Scale, Eriococcus azalea, and Cottony Azalea Scale, Pulvinaria floccifera. These small sucking insects feed on the bark and exude a sticky substance that turns the stems black. A scale infestation is indicated by sooty mold on leaves, yellowing of leaves, and twig dieback. This scale is most obvious from May through June when white egg sacs may be found in twig forks. Heavy infestations over several seasons may kill plants. Overwintering immature scales (nymphs) are about 2 mm long, gray, and are usually found in twig forks. This scale primarily attacks azalea and rhododendron, but has also been found on andromeda, maple, arborvitae, willow, poplar, and hackberry. Azaleas can tolerate low populations of this scale without injury, and if there are no yellowing leaves, no treatment is necessary. Beneficial predators and parasites will usually provide adequate control of light scale infestations. Examine egg sacs for holes which indicates control by parasites, and look for predators such as ladybird beetles. To control heavy infestations, spray dormant plants with a late oil spray to kill developing nymphs on twigs. If necessary a 2% summer rate of horticultural oil may be applied in July after all of the eggs have hatched. A grayish white, powdery coating or fuzzy white growth on upper or lower surfaces is Powdery Mildew (Microsphaera azaleae). This is more prevalent on deciduous azaleas and sometimes it affects the lower surface more. Entire leaves can be covered. In late summer and fall, small black specks may be found in the white areas. Powdery mildew is more severe on shaded plants. It is favored by the high humidity found in crowded plantings and damp locations. The disease is more severe during periods of cool, moist weather. These fungi produce spores on the surface of the infected leaves which are spread by wind currents to surrounding leaf tissue. These fungi overwinter in the bud scales for initiation of infection next season. There are a number of ways to manage this disease. Small bright yellow spots is a symptom of Azalea Rust, Puccininastrum vaccinii, a fungal disease. Orange-red pustules containing spores form on the lower surface of the leaf. This rust is only sporadically severe and typically infects deciduous azaleas. Control by avoiding those hybrids and species which are very susceptible to rust. Good air circulation is helpful. Triadimefon seems to help, but may not be registered for use on rhododendrons. Here is a link that might be useful: Van Veen Nursery

You can bury them,dig a trench deep and long enough for tree , wrap tree like they do when one buys a live christmas tree with twine and wrap with burlap all around. You have do dig around roots and will hear them cracking when you knock it over into trench ,then put a piece of plwood on top of tree as this makes it easy in spring when you unbury it and cover with dirt and it will look like a fresh buried body. It works ive seen it done as my family members did this in chicago, another way is to use chicken wire around tree and gather leaves and fill cage . Martin