I'm building a new raised bed for some Oriental lilies and I want to build the very best soil mix I can. I was hoping to get a little input from the folks here.
I feel that some background info regarding my seasons and growing conditions is very important to consider. I live up at Latitude 61 near Anchorage AK. I have a pretty short season. I typically have snow on the ground until May, so I get a late start. It's also very cool by the time Oriental Lilies want to start blooming towards the end of August (temps in the 50's) and into September (even cooler).
My current lily beds all run a soil ph of 6.8-7.0. This works excellent for all my other lilies (Asiatics, OT, LA, AO) and works ok for Orientals. According to everything I have read, the Orientals prefer more acidic soil in the range of PH 5.5-6.5. I'm wondering if the lower PH is needed beacause the Orientals have a real hard time taking up Phosphorus at the higher PH. This seems to be what I see in my Oriental lilies, a slight Phosphorus deficiency in the leaves. This deficiency becomes a little more noticeable as the temps drop. To me that makes sense because plants have an even harder time taking up Phosphorus in cooler temps.
I normally build my soil from leaf mold, compost, small bark nuggets, rock dust/sand and perlite. I was thinking of adding 10% Canadian Sphagnum Peat Moss to my usual mix to bring down the ph a touch.
Does this sound like I'm on the right track?
I love the Oriental lilies and don't mind doing everything right to ensure they do well.
Thx
