Sorbus ?leaf scorch ?drought ?something else

Hello there. Thank you for accepting me onto your forums. Please could I have some advice on the Sorbus Snowballs I planted approx 2 months ago? It's in a very exposed site. Gets very hot & also very windy. I have been giving the planting area a good soak every couple of days when weather's been hot, but may be I should every day instead?? Just don't want to over-water it + my soil probe's been reading around average 80% moisture. Please see photos... I thought it was leaf scorch, but now worried because some of the leaves are curling as well. Thank you

 

I can see you've been watering by the green grass nearby but at this time of year a new tree will need copious amounts of water for the roots to establish well and supply the foliage above. Ideally autumn is a better time to plant a new tree. The combination of heat and wind will be causing the foliage to lose water, resulting in the browning and curling of leaves.

Until the weather cools down and gets wetter, try giving your tree a good deep watering every three days or so. The equivalent of three 5l watering cans full of water poured slowly into the soil during early morning or evening will help. You could also add a mulch of organic matter or bark to reduce evaporation from the soil surface. Welcome to Gardeners Corner @Liz Bartlett .

 

Hi Plantminded and thanks very much for your reply & advice. I was too impatient to wait till the autumn I'll do as you suggest, thank you, and leave the sprinkler on it for longer + more frequently. I put that fluffy 'weed stop' stuff down as mulch. Presumably that's not organic. I've got some composted bark chippings, so think I'll put that down, then 'fluffy stuff' on the surface...

 

I think I’d use one or the other, you won’t need both. I had to look up what that fluffy stuff is . It does retain moisture which is the important thing. I assume you added organic matter to the soil while preparing the planting hole and that you have good well draining soil. Good luck with it, they are lovely trees, the birds will enjoy the berries!

 

Thank you. Yes, I read somewhere to use 50:50 of the ground soil/John Innes + I added some of that fungus stuff. I've got quite sandy soil & it's well drained. Hopefully not planted it too deep (with top of rootball level with ground surface) It's just I've read different opinions on that.

 

. actually, I think it was "Bullrush", not John Innes

 

You'll have to water copiously [those bucketfuls every few days] until you have proper autumnal and winter weather. You really can't overwater rowans of any type, unless they're sitting in a bog. Up here where I am, you can stick them in the ground at almost any time of year and they just grow. It isn't so easy in drier, hotter parts of the UK.
Light sandy soil isn't really the ideal unless you're in a consistently wet area, but the bark is a better mulch than anything else, and you can also keep adding regular mulches throughout the year to improve the soil and it's moisture retention.
It's thorough watering that matters if you plant at an unsuitable time of year though, especially if it's a decent sized specimen - which yours is, and is therefore going to struggle because there's more top for the root system to support. It's why autumn is best, especially if you aren't in the best location for those trees.
Once autum arrives properly for you, it should settle, but you'll still have to be vigilant in spring if you're in a hotter location, as any tree takes a year or so to establish well if you're in that type of location. You may still get some leaf scorch because of the wind, but it'll manage if it gets properly established - it would just be aesthetics

 

That's brilliant, thanks very much Fairygirl

 

Hi Plantminded & Fairygirl I'm a bit worried today, after a decent downpour of rain since yesterday evening, there seems to be quite a bit of leaf curling going on. Please see photos.. Do you think I'm suffocating it? There seems to be some healthy new growth as well though Don't think it's clear from the photos, but I did make a saucer-like indentation around the base to allow it to breathe. Thanks you

 

I think these are just symptoms of the tree struggling to get established @Liz Bartlett. I planted an Amelanchier in spring last year. Since early summer this year there have been quite a lot of yellowing and browning leaves, despite me deep watering. It’s in a windy location and gets hot afternoon sun, so will be selectively losing leaves to adapt while the roots develop. Your tree is also putting energy into producing berries and will try to hang on to them rather than leaves. I also don’t think you can overwater a Rowan, unless your soil is not free draining and gets waterlogged. In a few weeks it will go into autumn mode and lose its leaves, giving the roots time to establish further. I wouldn’t be worried about those symptoms at the moment, but keep watering .

 

My twenty-year old Sorbus cashmiriana always shows symptoms of stress at this time of year ; i.e. leaf-curl and browning.
I don't think the proximity of large established trees & shrubs helps ; all of which are competing for moisture in this unfortunately dry part of the UK .
Reading @Fairygirls comments I sometimes envy her climate !

 

Thanks so much for reply & advice Plantminded and Paul. Yep, I'll keep up with the watering. Suppose I was expecting it to look immediately healthier & just grow, when not confined to the pot from the tree shop, so thanks very much for your info

 

I'm not sure you'd envy it today @PaulB3 - but it's ideal for newly planted shrubs - and certainly for those rowans!
If you plant any shrub or tree in summer, it takes a fair bit of attention. Add in the fact that it's not a tiny sapling, and you multiply that attention several times. Add in an exposed area and it's more again.
Loooking at how dried out and yellow your grass is, it shows how dry the site is, and I'm guessing, your location/climate can be.
Rowans are resilient though, and I'm sure it'll be fine once you get proper autumn weather. How well it does in future years though, I don't know. Wind can fry foliage very quickly, so the 'season' you get with it may be far shorter than it should be.
I don't know whereabouts you are @Liz Bartlett, but unfortunately, it may not be the best choice for your location.

 

Oh dear! Thanks Fairygirl. I'll do what I can with it & we'll see. I'm in Stourbridge, West Mids. The grass usually isn't like it is now for very long, so fingers crossed...

 

I have to be honest @Liz Bartlett, but if that was mine, and I had a more suitable site for it, I'd move it.