Question From:
Neil Cook in Leopold, Geelong VIC
Nature of problem:
Japanese maple planted one year ago and new leaves falling off
Type of Plant (if known):
Japanese maple inaba shidare
Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
First year leaf growth falling off within weeks, leaves brown and withered
Soil Type (e.g. sandy, clay or loam) OR Potting Mix Type:
Clay (pre-treated with gypsum planting mix)
How often do you water the plant:
When soil moisture meter tells me its dry
How many hours of sunlight does the plant get each day:
Morning, part shade in afternoon (its located in corner of a small garden next to fence)
What type of plant is it:
Japanese maple inaba shidare (approx 10-15 years old when planted)
How long since you planted it:
January 2015
Have you fertilised? If so, with what and when:
Periodically with seasol concentrate
Is the plant indoors or outdoors:
Outdoors
Is the plant in a pot or in the ground:
In ground
What other treatments have you given the plant:
Mulched with washed seaweed (since planted) and pea straw (several months back)
Upload photo if available:
IMG_0316.jpg
Other Comments:
Purchased an established (around 10-15 year old) weeping JM from a respectable nursery and planted into clay soil in my garden which had been pre-mixed with a couple of bags of gypsum/planting mix. The plant lost its leaves almost straight away (which I partly expected due to it being almost autumn and the transplant shock). Tended to it carefully over winter (checked soil moisture with a meter and watered when dry), added seasol every couple months. New growth came around as hoped for in Spring – but after a few weeks, the new leaves began to dry up, brown and fall off. It looks very sorry for itself now and I’m worried (it was a family planted tree and takes pride of place in our garden). I suspect that its feet are too wet (as my meter tells me the soil is wet/moist for many days) and therefore I hardly water it…but I am worried about digging it out of its hole (its also very very heavy) and would take some effort to lift/move.
Not sure what to do – shall I dig it out and try to raise it? Or is it just taking a year or two to establish (as it is very mature)? Or shall I just mix in more gypsum/mulch?
Help much appreciated – I feel like i am letting down a very deserving and mature tree…
Answer: Hi Neil, You have a major problem on your hands,and it could be too late to save this maple. I don’t have much to go on, I don’t know how often you watered it or how often you used Seasol (see above). Seasol is not a fertiliser by the way. My guess is that the plant is drowning. If you dug a hole into a clay soil, this may well have created a sump that has filled up with water. Adding gypsum to the soil used as backfill in this sump would make things even worse. The way to use gypsum is to treat the garden bed in general with it – not the infill in a hole. Using a moisture meter would be a mistake in my opinion. The best thing by far is to dig several holes about 30cm deep and to look at and smell the soil. I strongly suggest that you dig this poor plant up immediately and pot it up into a large tub that will take its root ball. Remove any garden soil from its root ball, leaving any potting mix alone and use a Premium grade Standards Association mix for repotting. Immediately apply some Yates Anti Rot to try to stop the root rot caused by the flooding of the roots. The chances of survival are maybe 10-20% – if all goes well. Good luck, but you MUST act immediately – this has been an unattended emergency since January. When planting in heavy clay soils, always dig a shallow saucer-shaped hole and add organic matter and horticultural sand mix it all together really well and plant the plant mostly in the raised part of the new soil mix.
