We have recently bought a little Dwarf white pine, the one with the soft needles. We planted it on a mound and put a little bonemeal in the hole. We have read that they need no particular ground prep, so left it at that. Its about six weeks latter and we are starting to notice a yellowing of some of the needles. The yellowing is on all parts of the tree. The dirt has some clay in it, but is on a mound so it should have decent drainage. In the summer it is very dry. Does anyone have any ideas? We haven't fertilized it so maybe it is missing something.
Could be drying out or too wet. Check soil moisture, including inside rootball. Or could be too much fertilizer or wrong kind. http://www.puyallup.wsu.edu/~Linda Chalker-Scott/FactSheets/Planting fact sheet.pdf
It sounds as if it could have too much drainage. Some species of Pine shed two or three year old needles and can look pretty rough for a time. I have a dwarf P.strobus in my front garden and within 3 weeks of planting it was turning yellow and shedding needles. It is as right as rain now though, 5 years old and shed a load of yellow needles this spring.
I have a similar problem on a weeping white pine in a container. It appeared to be waterlogged, so I changed the potting medium to a commercial peat/manure mixture. Fertilized it lightly with a 4-2-2 dry organic mix (soy, canola, blood, bone, kelp and alfalfa meals plus rock phosphate and dolomite lime). After 1 yr no change. This year I added a bit of liquid fish fert that I give all the containers every 4-6 weeks during the growing season. Still no change. Tried spraying with just about everything I've got at one time or another. Still the same. I really need some help with this little guy.
Well it turned out to be just a spring needle drop before summer. I saw another pine that dwarf white pine and it was in a similar state. Since then it has come right along. Maybe putting yours in the garden will help it. I'm not sure if a lot of peat is ideal for a pine since they like a well draning mix and peat retains water, it is also acidic. If you consider where pine grow natureally it is pretty barren with little in the way of organic matter. Having said this books say they will grow in anything. Well good luck.
Thanks, Jamey. If I put it in the ground, I'd be putting it into dense clay, very poor drainage indeed. Interesting about the peat, 'though. I'll check the ph.