Reviving old plants

There are some very old plants in my garden that have been neglected for a number of years and are looking the worse for wear. Is there anything I can do to bring them back to how they should be or will they be beyond repair?

There is a mahonia (thanks to Jiffy for identifying it for me) which is more a collection of random twigs than an actual shrub. It looks reasonably healthy, as in it is flowering and has leaves, but as I said it is just a few stalks/twigs rather than a shrub.

Bergenias that have not flowered for the past 6 years to my knowledge. The leaves look healthy enough and there are two medium sized and one small one.

A rhodododendron that is about 3 foot high, has about 5 branches and produces a few leaves and flowers every year, but to me it's a lovely old thing and I'd love to be able to revive it. I've dug some ericaceous compost round it as deep as I could. It looks almost bent double, probably because of the fir tree branches above it, but I've lopped a lot of those off.

All these plants are under fir trees, get a mix of sun and shade and had previously been strangled by ivy and weeds (now cleared).

So, is there anything I can do to help any or all of them? The youngest they would be would be 10 years old and the rhododendron is much older than that, going by the look of it.

 

A good spring feed will help , blood fish and bone , or growmore is great as well , and keeping them watered in the summer and give them a good growing year just like us when feeling weak and feeble after a good meal we normally bounce back . Any hard pruning I would leave till next year with the shrubs as you may finish them off.

Bergenias need splitting and replanting the new looking ones and discard the old gnarly looking roots

 

Thank you Spruce. Growmore it will be then - my little terrier dog gets too interested in the blood, fish and bone mix and thinks there's something exciting buried there that has to be dug up. Do I split the bergenias now or give them a year of pampering too?

 

Hi Eve, You can cut Mahonias hard back. Give it a good feed, no need to water if your weather's anything like here! It'll respond by sprouting lovely new growth. I wouldn't risk chopping a rhodi.....

 

Thanks Noisette. No, I would be far too scared too chop the rhodi. It's survived so much neglect and still flowers year on year I'd hate to kill it.

 

Photos would be useful especially of the Rhododendron so we can see what may be affecting it. You can prune them once they've flowered to thicken them out but it's best done gradually over the course of a couple of years. It may be that the fir tree is sucking all the moisture and nutrients out of the soil, leaving nothing for the Rhodo (some slow release fertiliser will last a season) or it could be in the wrong place (you can always move it). I have a couple of Rhodos in my front garden which are near a Sycamore and they are looking very sickly so will be moved this year.

 

I've chopped old ones right back, and they have come-again.

Might just be over crowded? (Or too little light). Can dig bits off them and plant again or elsewhere.

Are you on Acid soil? If not they aren't going to like you full stop I'm afraid. (Yes you can try to treat them, but just a mulch with Ericaceous isn't going to be anything like enough). I guess the fact that it is still there after 10 years suggests that its happy in the soil? (If you don't know your pH are there other Rhododendrons / Azaleas / Camellias in gardens around you?)

 

Mahonia aquifolium (Oregon grape) is just coming into bud - mine are budding on the ends of their scraggy old stems, a bit like yours. If you postpone the chop for a month or two you'll enjoy the flowers first. Thanks for the reminder that mine need doing, I think I'll take them down to 6" stumps this year.

 

I've always thought that it's far more difficult trying to grow rhodis on clay soil, even acid clay, than on neutral loam or sand. They've got such fibrous root systems! They suffer far more often from drought than from chlorosis, but if the roots have been able to wander out into a nice, loose soil (ditto hydrangeas) it's surprising what they'll tolerate. Especially given an occasional, slow soak with an ericaceous fertiliser.

 

I don't think it's acid soil but have never tested the pH. I planted Rhododendrons, azaleas and Camellias in a nearby bed but I dug out about 2 foot of soil and filled it with ericaceous compost and they seem to be doing well. There are a few gardens in the village with Rhododendrons and some in the 'council' beds.

This is my poor old boy


The leaves are quite glossy and there are quite decent buds on it and it does flower every year.

 

We're on slightly acidic clay and Rhodis, Camellias, etc love it, judging by the profusion of them on our road. It helps that it's tree lined (with lots of old trees) so it's quite shady.

 

I reckon your soil is OK then

(I should have said "are there other mature Rhododendrons / Azaleas / Camellias in gardens around you?" as anyone can plant one of course!)

 

Hello (now I know who you are)

I would move the Rhododendron to somewhere where its happier - pref with dappled shade. It's very close to the tree in your pic. Looks like the leaves are starting to turn yellow so could also be suffering from chlorosis. You could prune it back once it's flowered but if you are worried that it might not regenerate, just prune one stem back this year to see if it thickens out.

 

Same here this year ,Lost in France , just Growmore . Blood fish and bonemeal must smell like a mixed grill to a dog , they go mad for it ! And Molly loves digging huge holes in my borders now !

 

Lost _ in_France, don't put much Growmore or Blood fish and bonemeal around your Rhododendron or anything else acid loving (Azalea, Camellia, Pieris etc) as both are a bit limey. I would honestly consider Merleworld's suggestion about moving the Rhododendron. They are REALLY easy to move having a mass of surface fibrous roots and no tap roots. There is an old saying that if you can physically move a Rhododendron then it will move! I know it's a thought to prune it back but I personally would. We have a place called Glendoick (www.glendoick.com) which I visit most years to marvel at their massive collection of Rhododendrons and come away feeling decidedly deflated at my pitiful efforts! The site gives you lots of useful information about the do's and don't re growing Rhododendrons. I have seen that they have pruned ancient specimens almost to the ground and then a couple of years later the specimens look wonderful again. Perhaps don't be quite so severe but give yours a good hair cut after it's flowered. Rather than being concerned about feeding it, make sure it doesn't ever get really dry (being in France, a distinct possibility?) and give it a thick mulch (good 4ins or so) with leaf mold, bark chip. Looking at you photo it isn't that clear but do bear in mind Rhododendrons do NOT like to be planted deep, better too shallow so if you do move it be careful. I was always taught to think where plants originate from. In the wild Rhododendrons mostly inhabit quite high places with large amounts of rainfall and forestry, they have evolved in areas with good drainage, high rainfall, varying degrees of shade and not a bag of fertilizer in sight!!
If anybody who has a passion for Rhododendron as I do is ever in Perthshire in April/May time do try to visit Glendoick they have some very rare and truly amazing Rhododendrons, many collected in the wilds of China by the ancestors of the current owners. They have some cracking Meconopsis as well (can feel a touch of green appearing around my "gills"!).