Hi, I would be grateful for any advice on what might be wrong with my garnet. It has been magnificent in previous years. But this year it leafed a lot later than any of my 30 other varieties and when it did leaf it was pretty sparse. In the last week the leaves have started to wither. I have sliced through one of the withered stems to check for Verticillium wilt but it looked OK. Any advice would be gratefully received.
Hi Ronnie, first of all how long has it been in that pot? I repot every two years as this keeps nutrients at right level. It also aids drainage and allows good oxygen levels to the roots. At this time you could prick the surface to ensure that the soil is not too compact. Have you watered a lot during the warm weather? Sometimes we can be too kind and kill a maple through over watering, especially if drainage is poor. I would let it dry out if you can between watering. We use a water meter to check hydration levels as some need watering every day and some every few days. It is a lot of work if you have a lot in pots but it's worth the trouble. Check moisture with your fingers if you don't have access to a meter.
Thanks Acerholic, It has been in the pot a while and all my specimens are probably in need of root pruning this winter. I plant in a mixture of 80% Westland Irish Moss Peat and 20% sharp sand/horti gravel so it is pretty free draining. In fact it can be too free draining as the organic matter disappears on account of microbial action. Apart from that, all the others are pretty normal so I am a bit stumped.
In fact, I have to confess that I lost my favorite tree this spring, a 6 foot Sumi nagashi, through lack of watering. A lot of plants, such as mock orange, will wilt noticeably and spring back a few hours after watering. Unfortunately, when an acre wilts through lack of water it is often already too late. So, overwatering is not one of my vices. I adjust watering according to the amount of foliage, temperature, wind the weight of the pot. Which water meter do you use? I tried one but it was totally unreliable.
I have looked at your photos again and the soil does look very moist. Think there is litchen on the surface, so that tends to make me think that over watering maybe the problem. I think that you may have to wait until next Spring to see if it survives. Repot it in the Autum and check for vine weevle. We use John inness no 2 (or no 3 on mature plants), peat, bark, horticultural grit and a sprinkle of michroriasil. Our pots are covered with large bark clippings. We have never used sand. Good luck.
Very many deaths are from over or under watering. Our meter was bought from Amazon at under £10. It is a Mapiro. Just seen it is now unavailable. Lots of other 3 way meters available, all at good prices. The Abafia is very similar to ours. Just seen it's available at a really good prime deal today at £6.99.
I stopped using peat in all my potting mix for maples because it holds too much moisture (even when fast draining). Some areas that are dry may get away with it. Trees tend to leaf out and slowly decline over years. A unseasonably wet Spring and real problems start to occur with serious decline. Now I use double ground pine bark, triple ground pine bark (pine fines or soil conditioner), haydite or Espoma soil perfector (expanded shale) and sharp silica about 2-3mm in size. Everything grows great. You can fix soil that retains too much water and or needs re-potted by mixing 60% sharp silica 40% pine fines and low dose of balanced organic fertilizer like 7-7-7 or 3-4-3. Mix up. Make holes with a spike 1/2 to 2/3 out from the trunk and pot wall. Gingerly push down and rock to avoid large roots down half way at 12 o'clock 3,6,9 o'clock positions. This gets oxygen and nutrients to roots and will combat root rot fungi. Depending on size of spike and if your soil is holding a lot of moisture you can make holes at 1:30, 4:30, 7:30, 10:30 positions down to 3/4 of total pot depth. This vertical mulching technique will reverse the decline and buy time to re-pot. I have done it with balled and burlap trees in ground where the ball gets too compacted and also done it to established landscape trees during an extremely wet spring in areas of the garden that stay too saturated in prolonged months of heavy rain with no opportunity to dry out. I have also heard of using hydrogen peroxide to add oxygen to the soil. But I like my tried and true method of vertical mulching. Has bought me time several times over the past 8 years and reversed decline in several Japanese maples.
Thanks, that is great information. I lived 6 years in Boston and when I arrived I was struck by the range of tools and machines and the way a carpinter will turn a strut to match a broken one on the porch. In the UK everything is pitch to the lowest common denominator and the best way to find a guy that can bang a nail into a bit of wood is to look for someone from Poland. :-). However, we are perhaps improving slowly. For example, mini cranes have started to appear on medium sized city building sites, only 30 years after they were introduced all across Europe, not to mention the ready mixed concrete silos. We 'aint half retarded over here. Please excuse my rant. It is just a prelude to me asking if any of the UK forum members can kindly tell me where to source: ground pine bark, expanded shale and sharp silica. They are probably not to be found in my local garden centre. Perhaps I'll try ebay. Thanks again. I'm learning a lot on this forum. I'll try to post pictures of some of my trees. Almost all are thriving. But in fact that Garnet was my first ever Acre and it may well be the repotting thing as Acreholic mentioned above.
Sometimes a picture helps, but not always. The bypass pruners are 220mm. Orchid or specialty shops sometimes sells soil components or a bonsai shop. Sharp silica is sometimes sold as filter sand. But it is not play sand (way too fine). It's also used in starting/ rooting cuttings and starting seeds. Wish I could be more help. Also, not being from UK, I was not familiar with your peat. I googled and figured it out. Also came across some reviews of people getting a bad batch. But most likely your garnet is in need of re-pot. When they are late to leaf out and it's been some time since re-pot, it's a must as it may not make to the next growing season. With that said, when you do re-pot you will be surprised by the rebound next season! (Speaking from experience) Also, I will check out my book Bonsai with Japanese Maples. I believe the author is from the UK so I will see what he recommendeds. I feel like crushed granite and fine river stone or even aquarium gravel comes to mind as possible components for soil mix, but I will check when I get a chance. My crumble test video would not upload. Soil should crumble when you re-pot and not stick together. Maybe this link to Google photos will work? https://photos.app.goo.gl/W6K6vSN3tKWXSgVu8
Just needs a good root prune and new medium , mine re pruned and potted from 2017 ( 60 ltr container ) Peat , Bark chip , JI no3 , works for my trees . Just use this as a parasol for my reticulates growing at the back of it , great sun blocker. If you want fine ground bark just put large nuggets through a branch shreder , thats what i do.
