I planted a 'Royal Star' almost 10 yrs ago when it was just a twig. It is in a fairly dry site and left pretty much to its own devices as it's in a isolated corner of the garden. For the first few years the flowers seemed insignificant and I was slightly disappointed, especially to the lack of scent. However the last 2 or 3 years, it's been gathering steam and last spring the flowers were very lovely, just smothering the entire tree. The fragrance was very pleasant - light but definitely there. It was so pretty, I was inspired to rejuvenate that corner of the garden and put in an entirely new bed. The tree is now about 5' tall & 4' wide - I'm sure its small size is due to the very dry soil in summer, as well as the fact that I've never amended the soil. In fact, it looks rather nice, like a bonsai specimen. On the other hand, my neighbour has a similar tree - m. stellata but I cannot be sure it's a 'Royal Star'- and it's more like 15'high. I gave it a very light pruning for shape - heck, I might even throw a bit of compost on it this winter.

> Another possibility is that the flowers can be damaged by frost, since it blooms early. If that is the case, move it to a more sheltered location where it may have some protection from late spring frosts. Some plants that are prone to frost damage to early flower buds benefit from being placed away from morning sun, into morning shade and afternoon sun. I don't know if that works for the early magnolias, but it supposedly delays the formation of the flower buds somehow, maybe by having the overnight low temperatures linger a bit longer into the daytime. However, since moving mags is problematic, and since this tree is apparently otherwise healthy, i.e. has good green foliage later in the season, it could be a problem with too much nitrogen or some other soil problem, but I'd shy away from fertilizer, unless you have a test done first. Hey, here's a study (just the abstract) on how frost tolerance of flower buds in apricots varies with different fertilizers. It's a little wordy, but it looks like you may really want to do a soil test and keep nitrogen fertilizers away from this tree. Potassium and phosphorus fertilizers had significant effects on the frost tolerance of flower buds. Potassium fertilizer played the most important role on frost tolerance, compared with nitrogen or phosphorus fertilizers. The results indicated that, the frost tolerance of flower buds following K2O applications was higher than that of buds treated with other NPK doses. Lower survival percentages of buds were found with nitrogen applications. The frost tolerance ability was found to be lower following fertilization at the higher doses of nitrogen. In all the investigated NPK doses, the level of K and Fe increased from January to February, in parallel with the frost tolerance ability of the flower buds, but decreased in November and March. Here is a link that might be useful: abstract:EFFECT OF NPK FERT ON FROST TOLERANCE

A lot of magnolias in this area need to be fertilized. It can take multiple applications of a nitrogen source before the desired level of improvement starts to be seen. Deep, moist fertile soil is what these woodland trees want. Whatever other factors might have been involved with your specimen 'Marina' is tender, two years ago there was much damage to plantings in the Seattle area. One supplier of it in California says on the internet they know it can take 15 degrees F. based on what they had seen down there. Hardy to at least 15 may be impressive or at least acceptable for coastal CA, but up here that is not an adequate assurance. Arbutus are basically trees of warm dry climates and situations, wetness and fungi are often problematic if a situation is not just right. Even the locally native madrones are having major problems these days on many sites.

My husband, who has past on, and I planted a magnolia tree when our children were born. I have successfully replanted it twice, one time to a new state in summertime four hours away. It has never had the luxury of being planted in perfect season or circumstances but has managed to survive each transplant. Perhaps slowing it's growth but in a few years it comes back full of life. It is dead to you if you leave it and sell your house either way. I moved the tree successfully by myself and with no equipment. If it's sentimental and you want to move it move it. If it dies, turn it into compost to place around it's replacement in loving memory. People who care more about the tree than the memory in which you planted it must not understand how those who plant with tears in their eyes drenching the soil feel about these memorial gardens. I've had brand new plants planted that have died, so planting anything anytime is always a risk. But if it's important to you move it anyway, talk to it (I did), take what original soil you can to reduce pH changes and add compost and drench it for the first few days, weeks, within reason. It should survive the move. Mine did. I was not so lucky with roses but I still wouldn't hesitate to try, if I wanted them. I didn't want to lose any of the original garden but added to it over the years. And it has given me a lot of pleasure knowing my husband's tree and memory was able to be with us. The magnolia and a few other species did the best. Good luck whatever you decide.