Why Plumeria Drops Leaves. I live in Nanaimo, B.C. Messages: 6 Likes Received: 0 Location: Greater Vancouver. Acidic soil is needed for it to grow well. Another possible reason is that the variegated leaves have suffered from sun scorch or suffering from lack of rain. So even though it's been hot here in the day, I decided my mountain fire pieris wasn't going to make it if I didn't move it. My Pieris Keeps Dying. While some leaf loss is normal, there may be many reasons for a plant losing leaves, and not all of them are good. I have a Pieris Japonica "Dorothy Wyckoff" and last year it was lovely. Hi all, I'm hoping you can help me preempt a gardening problem I've had for 3 years running. This year however something is wrong with it. I have a 8 year old pieris (not sure which flavour) which has been very happy with me until this year. It just doesn't look well. Q: Could you please give me some reasons why a katsura tree would lose its leaves prematurely? The leaves are turning brown with specks on it. There are various reasons for yellowing leaves in the Pieris ‘forest flame’.It likes an acid soil so you need to feed it with a lime-hating plant food. Re: Pieris japonica 'Dorothy Wyckoff' I am hoping somebody can help me. If you've ever seen a plumeria plant (Plumeria spp. The leaves are also starting to fall off. As you can see from the photos the new leaf growth is yellow (from the original beautiful scarlet) and over the last two weeks the leaves have started to brown from the tips. I have an established Pieris Forest Flame (approx 10 years old) which is in a large tub. I am pretty confident it has not dried out and I feed it as prescribed. The tree is situated in a sunny unprotected area, uphill from the ocean, so it does get the wind. Last summer the foliage remained green but it did display a mass of cream coloured flowers. This spring its appearance went downhill and I was sure I was going to lose it so I gave it a top dressing of fresh ericacious compost and some liquid feed. The leaves are getting brown on the edges with spots,there has been absolutely no growth whatsoever this whole year, so I dug it up and planted it at 9:00 p.m., ha ha I'm a night time gardener, only time its nice and cool! Has your Pieris 'Forest flame' been growing in its current position for long ?. Discussion in 'Outdoor Gardening in the Pacific Northwest' started by kanayo101, Mar 18, 2010. kanayo101 Member. When leaves drop, it can be quite disheartening, especially if you don’t know why it’s happening.