The new app packed with trusted gardening know-how
North Yorkshire
Essex
Devon
Surrey
Greater Manchester
RHSAdviceTeam (RHS Staff)
A lot is made of growing agapanthus congested in pots to encourage good flowering but I fi
Hi Ctace. Your topic is more in depth and history based than we can help with in RHS Ga
Large quantities of nitrogen can encourage rapid, soft growth that is less resilient to
Sounds like a case of cushion scale. Follow our control guidance on this page - ...
I'm glad your wisteria flowers well. pruning does help See our web profile on prun
if you have tried all the control methods above then it may be worthwhile removing the
Yes, only put paper and card on your compost. Plastic coatings are not compostable. Check
Exiciting! These little plants are known as kiki. Once the leaves are about an inch or
Your trachelospermum question might be better answered by our online community if poste
Once the flowers have faded cut the flowering stem off at the base.
There are quite a few plants that do well in alkaline soils - have a look at the RHS we
For correct treatment of iron deficiency check out the RHS Web ...
It appears that you
Glad to hear that, despite the trials and tribulations, you are still thrilled by plant
Feed with a good rose fertiliser such as Top Rose in February or March and again in ear
The lower leaves of the cordyline can be removed as they die off to form a trunk. If th
Yes, it has been particularly wet year and we have seen more peach leaf curl than usual
The trouble is that mistletoe berries are usually seen at Christmas when they are used
Your bay trees are probably suffering from establishment problems - see the Establishme
This is indeed a tricky one to identify without photos. They could be something that ar
Peeling back the turf and having a look for grubs is the simplest way to tell the
Thank you to everyone for their feedback. We've now had chance to review the pruning gr
SOunds like tortrix moth caterpillars - see https://www.rhs.org.uk/advice/profile?PID=8
Bit of a mystery. Cyclamen will not thrive in the shade of evergreens. In very impoveri
It does sadly sound like your viburnum is unlikely to recover if the browning is gettin
I have searched the advertisement in the March 2016 issue of the magazine and cannot fi
Sounds like you already have the makings of a fine wildlife feature. Since the liner is
Cut back new growth by half in each of the following two or three years after planting
The only quick way to be rid of weeds in the lawn is with a weedkiller especially for l
acacia is a fast growing tree especially in London but its a shame that while it is you
Hi vikkib74. Clematis armandii falls into pruning group 1 above; so not much t
Mushroom compost is mainly manure, so I'm not sure where the coffee grounds come in, he
It would be preferable to turn the compost heap in late spring, summer or autumn becaus
Dear S
Hi Binky. The good news is that this is usually a physiological problem; so plants stru
If you intend to keep the fruit in pots then many will fruit in their first year simply
You an plant into the ground in late April/May in a sheltered spot. However, they rarel
Oh dear Marion. I'm sure you're not alone after this wet winter. Spike the lawn now to
When apple and pear trees are renovation pruned, they can have or develop watershoots.
Any well-drained soil is fine, so just avoid sticky clay (but it will cope with this to
Do bear in mind that some defoliation happens naturally, but it is the patches that are
Hi Andrea We are not aware that Phalaenopsis are toxic to children or dogs. In general,
Sadly, there is no new information available to help overcome holly leaf blight. The tw
This is a late reply for Heather but may help other readers. The simple answer is no, d
Wisteria roots, like their shoots, can be pruned. I'd advise in February before new gro
Hi Ducks and moorhens are protected between February 1 and August 31 each year u
Hi
Ducks and moorhens are protected between February 1 and August 31 each year u
Dear Qlchina, Currently in the UK there are no growth regulators licensed for use by ho
Hi Jake. Unprocessed is likely to mean it hasn't been composted. This means it is fine
Hello Chafer grub and the larvae of the crane fly can cause brown patches in law
Hello
Chafer grub and the larvae of the crane fly can cause brown patches in law
Dear HbLee, No need for a diapause with a Phalaenopsis. Jsut follow the general care in
Hello Late autumn is an ideal time to lift lilies. Cut back existing stems to ground le
A number of plants go under the common name ‘castor oil plant’ but I a gues
Apples count as "soft greens" so don't overload the heap; they should be no more than 2
Hello Where a pruning group is mentioned in a web profile, the description of th
Where a pruning group is mentioned in a web profile, the description of th
Dear Naked Ape, Phalaenopsis orchids can flower for a long time if the growing conditio
Remove the larger ones (I'm afraid they won't ripen off the tree) but keep the pea-size
You can allow the Japanese knot weed stems to dry out and shrivel up in the garden, on
It can be devastating to lose trees and shrubs. Ideally leaving the area to "rest" woul
Bt is not currently available to home gardeners in the UK. It is formul
Peat is not used as much as it used to be for ecological reasons:
Hi Christopher, the damage to your lawn is most likely being caused by
As suggested above under pruning summer-fruiting types, simply loop the tops of long ca
Box tree caterpillars only feed on Buxus spp. A very common and similar looking caterpi
Hi Anonymous. This problem to weather conditions, which could include late frosts. Like
A light rake shouldn't be a problem soon after seeding but if seed has already begun to
Liming is unlikely to have any effect at reducing major potato pests such as slugs, pot
You don't want the roots to dry out, or to be exposed to cold frosty weather during win
Hi Mr Taylor Welldone! Lovely to hear that you've been so successful at this year's
Hi Mary The next stage would be for you to send pictures or samples to the
It does indeed sound like your shrubs have powdery mildew so follow the advice given on
See conversation
Hi Sam Box tree caterpillar only eat box and have not yet been reported in Devon. As th
We are in the process of moving away from Pruning Group lists for our web based pruning
PS Do see Roerebecca's response above as this includes some additional, pracitcal thing
Hi Lexi. It does sound like the roots might have drowned - well investigated. Good drai
This is actually a perennial grass (which is evergreen) and not a bamboo - it is a
It is possible the wilting is due to the wet soil. We'd recommend using a soil based co
Wisteria need moisture retentive fertile soil to help produce flowers. Pruning is vital
Thank you for your comment which has been passed to our web editorial team. P 87
Thank you for your comment which has been passed to our web editorial team.
P 87
Hi Ladybird196 I'm afraid that this method of slug and snail control is illegal
Hi Ladybird196
I'm afraid that this method of slug and snail control is illegal
The yellow balls you describe are most likely to be controlled release fertiliser added
Hi Little Weed. Did you email RHS Gardening Advice at the same time? Anyway, if not, do
Hi Meg Do check the problems section on our
Hi Sukol. Do take a look at our Replant Diseases pag
It sounds like a classic case of high temperature injury, caused by warm weather and dr
The odd branch shouldn't be causing any major problems and the water quality sounds ok
The position doesn't sound great, I'll admit. If you've got a better spot for it, move
Hi. It does indeed sound like a less weedy type of oxalis. RHS members can send in (pos
Bacillus thuringiensis is not available to home gardeners in the UK, so unfortuna
Indeed, and there is only one generation of sawfly a year and the plants will not suffe
Long-term the trees will not be doomed, but in some years the trees might look&nbs
As no fungicides labelled for use on cucumbers you have done the best thing,
Tree ferns do sometimes come with a few 'hitch-hikers' in the form of other small ferns
From the description it is likely to be horsechestnut scale. Acers are very susceptible
A rotary mower copes best with an uneven surface. You may need to consider lawn repairs
Madame Alfred Carriere is a very large climber, usually a very prolific flowerer so if
There is no facility to attach photos but if you were an RHS member you could
Warm days and cold nights early in the growing season can lead to distorted fronds emer
Hi Magnolias resent root disturbance of any sort but should recover if only a fe
Magnolias resent root disturbance of any sort but should recover if only a fe
Hi Sam. Although when used as directed most garden weedkillers should be safe to use ar
Passion flowers vary in their hardiness and may be damaged in a cold winter, but&n
A mixed hedge will need careful and moderate pruning at this time of year, but can be h
Removing the infected fruit will help remove infection and thin out the fruit, check ou
Honey fungus does seem to attack most plants, particularly where there are high levels
It sounds like your plant suffering from drought try watering it, possibly including a
Oriental poppies have been suffering severely from downy mildew. Initially seen as ligh
If the oldest needles, then likley to be environmental stress. If new needle could be a
This does not sound like willow anthracnose . See the RHS Web Profile for more informat
Hello Hahoo, We have not seen any commercially available pheromone traps for box
Hello Hahoo,
We have not seen any commercially available pheromone traps for box
We provide information on the products gardeners are able to buy and use legally in the
Have a look at our profile on planting up containers: https://www.rhs.org.uk/Advice/Pro
There is some support: by law the paving must be permeable or, where non-permeable mate
Hot composting can kill many fungal spores, and if it can reaches and sustains temperat
Place in a brighter spot indoors or put outdoors over summer, initially in part shade f
Hi there. Our experience suggests that if you are getting the problem every year and th
Looks like you had a great day. Best of luck for this year's show. From Leigh, RHS Gard
The National Collection Holder is recording sightings of this disease in
That is a bit of a worry. If there is no improvement by the end of June I'd be inclined
Oh dear, that's a shame. Could be an overwatering problem or maybe wind scorch if they'
Hello compben, I'm afraid there are no preventative measures available if you wis
Thank you for the report - it has been added to our database. The first records of cate
Hi John_10 Moss is always likely appear in warm/mild damp conditions. Where the lawn is
Hi Katie. There's usually a 'better late than never' principal for most late plantings,
Hello, Thank you for submitting your sighting to us at the email address, you wi
Hello,
Thank you for submitting your sighting to us at the email address, you wi
Hi Mrs Lowe. Best to contact your local bee beekeepers as, if it's a swamp, they will o
Do try following the cultivation advice above for sucess and the problem section. They
Consider verticillium wilt as a possibility. F
Unfortunately, these pendulus cotoneaster are usually grafted to the top of a straight
Tree peonies are very difficult to move successfully, particularly as this peak in thei
That was meant to say 'growing points', not 'growning (groaning?!) points'! Helen
It is still early days for non-evergreen agapanthus to be showing foliage. Provided the
Hi Sarah. Have you had a look at our page on growing peonies? Visit ...
It is really best to leave a vegetation free circle around the eucalyptus so you can pr
This is a new one on us - green mould could be linked to rotting material in the compos
Hello The symptoms you describe could be due to a variety of causes. Diseas
Hello Renold Alder leaf beetle can be very difficult to control on tall tre
Hello Renold
Alder leaf beetle can be very difficult to control on tall tre
Just ensure that there are no tears - so a clean cut with a pruning saw should suffice.
Iris are a large group of garden plants that have many different growing conditions but
Hollies can be pruned hard to renovate (see our webprofile on pruning evergreens),
Probably the green spruce aphid, advice on this species can be found at
Dear Zerafa158 It's very difficult to guess
Dear Zerafa158
It's very difficult to guess
Hello WillberforceBaggins Tapeworm, roundworm and other parasites can be a risk
Hello WillberforceBaggins
Tapeworm, roundworm and other parasites can be a risk
It's weather dependant, but 2-4 weeks is typical. The individual blooms will fade and s
It is quite a tricky and challenging area you are planning to garden in, especiall
Hi Laying new turf on unprepared ground is a recipe for disaster. In any case, t
Laying new turf on unprepared ground is a recipe for disaster. In any case, t
We believe this to be an old wives tale. The branches are generally splayed out on eith
Hello amna, You might find the following page on unproductive fruit trees helpfu
Hello amna,
You might find the following page on unproductive fruit trees helpfu
Hello Blanchy Hostas are known to be particularly palatable to slugs and sn
Hello Blanchy
Hostas are known to be particularly palatable to slugs and sn
Have a look at our webprofile on Brugmansia for hints and tips: ...
And don't forget you can take a look at the
Have a look at our 'Climbers and Wall Shrubs for Shade' webprofile for inspiration:
Although cordylines are well known for new growth breaking through frost damaged s
Do not pick off the shoots. Pinch them back when they reache about 40cm to promote
Do take a look at our Ornamental Grasses profile for
The best time to move evergreens is in spring or autumn. See our web profile on moving
It is best not to let young fruit trees crop, they need time to grow good roots and a f
It sounds that with continual severe infections your tree has been suffering from
Hello NewbieGardenOwner23, Generally it’s a great idea to encourage wildli
Hello NewbieGardenOwner23,
Generally it’s a great idea to encourage wildli
Mulberry trees are sometimes grown in pots but usually don't grow large enoug
There are many fertilisers you can choose for a top dressing around young trees and shr
Copy and paste this link into your browser address bar and press return to see the info
Talk to your supplier to ensure you know where the trees have come from (possibly in a
Yes, we agree with Mr Kelly's reply that glyphosate ought to do the trick. If you didn'
Thanks I can see that you have contacted Gardening Advice as you are a member, so I hav
Wisteria sinensis produces its flowers before the leaves appear; its stems twi
Hi None of our current crop of plant scientists can recall the research you are
None of our current crop of plant scientists can recall the research you are
Hello While the ground may be flooded for 2 weeks at a time the soil is likely t
While the ground may be flooded for 2 weeks at a time the soil is likely t
Hi Carrot Top. The best thing to do is, from the above "In years when re-potting is not
The fungus can reside within buds but it is also dispersed via spores through the air.
Black marks could be apple scab but the curling leaves might be another problems. I'd s
Thanks for that. We've had several Eucalypts blown down here at Wisley. British Gardene
The lower leaves of the cordyline can be removed as they die off, to form a trunk. If t
This is a lovely idea but in practise there can be problems. The first is that leylandi
The collapse of your runner and French beans points to a root/stem problem such as 
The lawn may be brown because the turf was damaged by animals such as birds, foxes or b
Bay trees are often attacked by a pest known as a bay sucker and the classic signs of t
As you're unable to burn them. the best way to get rid of bramble roots is to bag them
Hi Mrs Bee. Thanks for sharing your success! Leigh in Advisory
Hi John. Not a good idea to add horsetail (aka mare's tail) or other pernicious weeds t
There is no need to routinely prune this tree. If you need to tie in any straggly branc
We are not experts on the subject, but the set up cost a ground source heat pump appear
Your greenhouse is very small, so there may be a mismatch between heater a
Cut back your salvia near to the base where you may see buds appearing. T
Tree roots seldom cause any physical damage to house foundations, the problem is the am
The cracking of the bark could be just caused by extremes of soil moisture levels. Make
Deadhead tulips after flowering to prevent seed production. See our tulip cultivation p
Hello I think there could be a number of causes. Citrus like it cool and light i
I think there could be a number of causes. Citrus like it cool and light i
Sounds like you did a very successful renovation. The lack of flowers for a season is t
Hi Peter The web profile refers to ‘Ornamental grasses
Hi Peter
The web profile refers to ‘Ornamental grasses
Hi Peter The web profile refers to ‘Ornamental grasses’ in the accep
The web profile refers to ‘Ornamental grasses’ in the accep
Excellent suggestion. The information has now been added which is hopefully of more pra
Thanks for your comment. We've amended this to make it more relevant for a wider range
Have you seen our webprofile on plum aphids? https://www.rhs.org.uk/Advice/Profile?PID=
Clive Turner Powdery mildew symptoms on photinia are usually seen as a whit
Clive Turner
Powdery mildew symptoms on photinia are usually seen as a whit
Hi Chris. Think you might have intended to reply direct to Capt_Clarke below. Like you
Miss J Best The products Fungus Fighter Plus and Fungus Fighter Concentrate are
Miss J Best
The products Fungus Fighter Plus and Fungus Fighter Concentrate are
Basil and coriander can be grown indoors on a sunny windowsill and of course, don't for
Hi Chris, It is not unusual for Clematis to be affected by scale insects. T
Hi Chris,
It is not unusual for Clematis to be affected by scale insects. T
Hi Mrs Walton. Moles can, indeed, be a nuisance. All the options we know of are mention
Hi Paul It perhaps sounds severe but, as mentioned in the section on overwintering, onc
Hi Miss Tullett, Given the complex nature of these issues, we are unable to help from the
Unfortunately, we don't have great knowledge on dealing with pests
Do prune as per the standard 'how to prune' section above. If a
They do keep growing, I'm afraid. Just keep cutting the new shoot
Sorry for the delay in responding. We have now added a section on
Hi, for renovation pruning see our webprofile on renovation pruning y
Hydrangeas grow best in shade but won't put on growth if the so
There is a new product being released by Bayer in 2015 which is
Trachelospermum prefers neutral to slightly alkaline soils, but if your
Your tree is probably suffering from establishment problems. Please see
We would suggest not adding cardboard or paper with a glossy finish
Hi Blackbush, Heavily printed paper and cardboard is best avoided as
Hi Matty and Anonymous, just to let you know that there are more
Hi Melly. It's perhaps a little lost above, in the cultivation se
Hi Dennis - you can cut off the old flowers and deciduous (dying
Greentech offer root barriers. The product would also be suitable to
Thanks for your input Dave. For more planting advice, Sam, take a
Thanks for this!
Yes, you can take a look at our advice at ...
In February, your honeysuckle can be pruned down to as low as 60c
Sorry for the delay in responding. Do take a look at the problems
Do take a look at our Non-flowering woody plants webpage at ...
Me again! Thanks for your comments. As well as eating,
Thanks for your comments. As well as eating, don't forget the ...
Sorry that your comment wasn't picked up earlier, and although your
There's a useful list of hedging roses in RHS Find a Plant. Cop
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.