Phil McCann from the RHS answers your gardening questions

[RachelMumsnet]

The Royal Horticultural Society (RHS) is the UK's leading gardening charity. As a charity the RHS helps to bring gardening into people's lives and support gardeners of all levels and abilities; whether they are expert horticulturists or children who are planting seeds for the very first time.

Phil McCann, PR Manager for RHS Gardens, with support from gardeners at the four RHS Gardens, will be answering questions from Mumsnetters throughout this week. Whatever your query - from carrot fly to container vegetable growing, wisteria pruning to water-free gardening - Phil and the RHS team are on hand to give you advice and information.

Phil, who was previously Assistant Producer on BBC's Gardeners' World, is a trained horticulturist, a keen and knowledgeable gardener and allotment holder, a member of the RHS Vegetable Trials Committee and garden writer. Phil will be checking this thread each day and answering your questions on this thread along with his colleagues at the RHS. Final day for questions is Monday 5th July.

In return for posting a gardening question we will automatically enter you into a prize draw to win a pair of tickets to the RHS Hampton Court Palace Flower Show next week. Each ticket will allow an adult and two children under the age of 16 into the show free of charge. Tickets will be valid on any day from Thursday 8 July to Sunday 11 July. For more information about the show visit www.rhs.org.uk/hamptoncourt.

[midnightexpress]

Oh, please answer goingpostal's question because I'd like to know hte answer to that one too!

[JaynieB]

Hello
I've just been offered an allotment - its been slightly tended for the previous year, but before that was disused for several decades.
The soil is very impoverished, very acidic (ph may be less than 5, which was as low as the test kit went).
Where do I start?
Thanks!

[solo]

Hi, I have two questions please.

1. What is the best/easiest way to kill off a garden of weeds?
   
   
2. I have many Leylandii trees that are way taller than my house and I'm concerned about their roots. Do they grow down or out please? (please say down).
   
   Thank you.

[PrettyCandles]

Hi Paul

The back of my house faces SSW, and the garden has trees growing along the fence, but outside the garden, on two sides. Consequently the house is in sunshine all day, but the bottom of the garden is not only in perpetual shade but also competing with trees. I like fragrance, but more importantly need some year-round colour. Other than spring bulbs, what can I plant in this dead zone?

Also, nothing thrives on the WNW-facing side of the garden. Plenty of afternoon sunshine, but, again, everything I plant has to compete with the neighbour's trees. If I apply fertiliser, will my plants benefit, or will my neighbour get a bumper crop of apples?

I have slghtly alkaline, clay soil (but not disastrously clay-ey).

Thanks!

[liath]

Hi,

I have an acer palmatum in a pot that is looking very sick this year, the leaves are brown and dropping off. I'm not sure what to do to help because I don't know what's make it so ill . I fed it in the spring & may have overwatered it. It's been in the same pot for 2 years. It is in the sun until 1pm. Any idea what has caused this and is there any hope I can save it? Would planting it out make it better? It was a present for DH & I don't want it to turn into a metaphor for our marriage .

Cheers.

[Longtalljosie]

Hi Phil,

What are the little black beetley things all over my lemon tree and other plants (picture on my profile) and how do I get rid of them?

Thanks

[PhilMcCann]

Dear CMOTdibbler,
Many thanks for asking a question - and what a great one to start with! Weirdly slopey, low maintenance, drought tolerant and cats - you don't ask for much! There of course plants suitable for your conditions - there are plants for every situation - and periwinkles take some destroying. Gorgeous purple flowers ( you can also get white varieites) and stringy branches of glossy green leaves. As a rule of thumb, plants with silver leaves are usually drought tolerant so check out perovskia, caryopteris and even olives if you fancy something Mediterranean. And if the dry weather continues it won't just be the North West where hosepipe bans may come into force. If you are ever in Essex check out our garden at Hyde hall - they have a magnificent dry garden crammed with just the plants you want.
www.rhs.org.uk

[trice]

Is there anything I can do to stop the sawfly eating my gooseberries next year?

[PhilMcCann]

Dear jonicomelately,
I can sympathise - I have two boys, one 13 and the other 5 and both like their footy and cricket. Plants do get damaged but some hold up better than others. Hebes are fantastic because they are tough, available in loads of colours and do bounce back after a wayward shot ( don't mention the World Cup!) Your conifers may be nice but if they are plain green and large do consider getting rid and adding more choice types. RHS Garden Wisley is the place to see almost every plant you could ever want and the staff there are incredibly knowledgeable. Your lawn will get a battering and regular mowing ( leave it long in dry weather as it survives better), aerating and getting rid of any moss will help keep it looking good. If you do feed it check out the manufactuers instructions as to danger to your children and the dog. And I'm not letting you go without a word about your lapsed membership -how could you?! So here's the deal to get you back - you know that a visit to one of the Royal Horticultural Society's gardens makes a fun-filled and good value option for a family day out. Throughout August, children under 16 get in free to all four RHS gardens when accompanied by an adult and a calendar of special family events is taking place all through the summer. You know it makes sense - might see you there.
www.rhs.org.uk/gardens

[PhilMcCann]

Dear MayorNaze,
You are not alone - trust me - there are many people who are continually battling against weeds on their plots. And you know what? We all have to learn to live with the fact that weeds will appear on our plots and unless you spend every hour of every day at the plot, they will be there when you enter the allotment gates. A few won't harm, will increase the chances of wildlife and give the other 'pristine' plotholders something to moan about! So don't get too upset, keep cultivating only what you can manage and cover any spare ground with black plastic, or those large plastic sheets from a leading DIY retailer. The plastic will smother the weeds and the soil will be ready for when you have the time to start cultivating that part. It's either that or give up everything else in your life and spend every hour down at the plot - and I'm not suggesting you do that. You'll get more info at our Grow Your Own weekends being held at the four gardens this weekend. There's loads of information and most importantly, staff who know their onions ( sorry - had to write that somewhere!!)
Check out
Harlow Carr:apps.rhs.org.uk/rhseventfinder/details
Hyde Hall: apps.rhs.org.uk/rhseventfinder/details
Rosemoor: apps.rhs.org.uk/rhseventfinder/details
Wisley: www.rhs.org.uk/Gardens/Wisley/What-s-on/Berry-weekend

[PhilMcCann]

Dear JustineMumsnet,
New Dawn is a gorgeous rose and can be grown in a container. The thing is that whatever manageable size of container you choose (20in pot is OK) you will need to keep an eye on the watering. When roses get stressed due to dry weather they fall prey to mildew a lot easier. I''m not too worried about you planting it in the soil as a foot and a half of soil is pretty good - sure, roots will rot if sitting in water but the rootball should be extensive in that depth of soil. So, give it a go in the ground, keep an eye out for stressed plants ( waterlogged soil = limp leaves) and enjoy the rose. I was at RHS Garden Wisley last week and I'm not kidding, you could smell the perfume from the rose garden a hundred metres away.
www.rhs.org.uk

[MayorNaze]

Thank you Phil -I have just come back after a quick weed

[PhilMcCann]

Dear ASmallBunchOfFlowers,
Sadly foxes are in the news and getting more common in urban areas. Once established in a garden they can take some shifting and although they can eat mice ( another garden pest for some) their calling cards are horrid for both parents and children. It's a tricky one but I would immediately fill in any holes they make to prevent a den being established and never leave food out for foxes ( I'm sure you don't but maybe ask neighbours if they are - and ask them to stop)
Chemical deterrents rarely work and need frequnt applications but a friend of mine has used a sound deterrent to good use. That was two weeks ago - my concern is that the foxs will get used to the noise.
Therefore, keep up with the paving slab and netting deterreent, try a sonic deterrent, never feed the foxes and keep filling in the holes they make. They might get the message.

[PhilMcCann]

Dear CuppaTeaJanice,
I tell you what - your name has inspired me to get a cuppa and sort this out in a minute...
that's better.
Right, deep breath, here goes:
Brambles: cut them down and dig them out ( although you do say 'large' garden so that bothers me; Pendulous sedge: same again; or you can use a chemical that kills anyhing that is green ( so be careful where it goes) but degrades on contact with the soil. Look for the active ingredient called glyphosate. I don't like pouring chemicals all over the place but if you have to get rid of weeds then that is the one to look for ( it has various trade names but look on the label for glyphosate)
Now for your horsetail - you might need a sit down after this one. It is one of the Earth's oldest plants and a right old survivor. Every section of root left in the soil will grow another plant and every stem fractures into sections that, you've guessed it, grows another plant. Let it bloom and you get more plants. Actually, a sit down and a biscuit might be a good idea. Chemicals will knock it around a bit but it will come back. Your best bet is to keep hoeing or strimming the shoots off when they are young. This will eventually weaken the plant. If using chemicals on it crush its stems first to allow the chemical to penetrate the glossy exterior. Or...live with the lovely little age old Christmas tree-like shoots. I thought so, get digging!
Once you 've got rid of, or at least tamed that lot try a cotoneaster for ground cover. Red berries, tough stems that smother the ground that will help keep new weed shoots at bay.

[PhilMcCann]

Dear SchnoogleDyBroogle,
Wisteria is a great plant. They do move and the best time is November when all growth has stopped. Make sure you get as much of the rootball out and intact as possible and get it straight into well prepared soil in a new planting hole as soon as possible. RHS Garden Hyde Hall has a cracking wisteria along a pergola and Wisley has a couple in their smaller display gardens.
www.rhs.org.uk
Love you name by the way!

[PhilMcCann]

Dear Wilbur,
Magnolias have to be one of my favourite plants, and the area of particular expertise of the RHS Director of Horticulture so I have to tread really carefully now! Yep, you can prune but if you do please take out complete branches and not just fiddle around with the tips of branches. Dropping leaves is natural but do make sure it is well watered - I guess your clay soil sees to that. If it drops the lot let me know. You can try a high potash feed to encourage flowers - granular feed made for tomatoes is great.
Roses: it's surprising how much pruning plants put up with. Prune half of the growth away in late autumn and move the remaining plant to its new home. You watch it regrow!
Organic slug pellets: I use them and to be honest, they can't legally be sold as organic unless certified. Of course, anything unnatural in the garden can have an effect on wildlife, but if you have to use pellets they are the ones to go for. Rest easy Wilbur, all is well in your garden and am I right in thinking you have new loppers or secateurs? You sound like you need to get pruning.

[PhilMcCann]

Dear nigglewiggle,
Magnolicide suggests you are killing them - surely not!
Magnolias are superb, especially when they avoid the wind and frost of spring. There are so many to choose from but I like a smaller growing one called Magnolia Stellata. It likes a sunny spot, well drained soil and isn't fussy about the acidity of soil ( many magnolias are!) It grows to around 3 metres and is the one for smaller gardens.
Magnolias are better grown on from small plants as they don't like being transplanted when large - something in a 10 litre pot and about a metre high should cost about £20 (a bit vague but it does depend on where you shop) You can find every magnolia name and where to buy them at: apps.rhs.org.uk/rhsplantfinder
And don't kill the next one!

[PhilMcCann]

Dear 43Today,
Only two questions - some of you lot have crammed three in ( and you know who you are!)
Perennials in pots: such a choice but whatever you choose make sure you have good drainage and plenty of root room - watering may be a bit of task in scorching weather but to be honest, quite relaxing on a summers evening. I love agapanthus -I saw them at Tresco gardens a few weeks ago and they look terrific. Gorgeous blue pom pom flowers on stalks a couple of feet high. And they are low maintenance - my own plants have had nothing done to them for six years and they still bloom in July. Pinks ( or old fashioned carnations) grow well in containers and I've just planted up some purple flowered scabious into a couple of containers. They will flower all summer if I keep deadheading them.
As for your tree - you've gotta go for an Amelanchier (also called Snowy mespilus) It has coppery leaves in early spring, white flowers in late spring, gorgeous green leaves in summer and fantastic autumn colours. You can't beat it, it won't rip up your block paving and you'll see one at RHS Garden Wisley www.rhs.org.uk

[PhilMcCann]

Dear Lymond,
Four children under 7 - how do you manage to do anything in the garden? First of all you have to keep on top of that dreaded ground elder - it's a full time job in my own garden. An hour a week will keep it tamed. Second is making sure nothing goes without water as lovely plants can suffer in this hot weather. Only water newly planted plants and the little stuff - the big 'uns can fend for themsleves. Thirdly, enjoy the garden. Live and let live, let a bit go wild and enjoy the increased number of butterflies and moths.
I have to say you will need a day out in summer after all that ground elder weeding so go to one of 'our' gardens and take the children in for free. It's all in August and I promise the gardens will be an inspiration www.rhs.org.uk/gardens

[PhilMcCann]

Dear madrush,
Lawns - love them or hate them, they are a big part of gardening. And where there's a lawn, there's moss.
Of course you can get someone in to sort it out - but it will cost a few quid and chances are they are lobbing about lots of chemicals. It's not for me.
You can rake and scarify until your biceps bulge and your back aches - but moss will come back. You have to treat what's causing the moss. It's bad drainage and your shady spots. Aerate the soil, that's making holes in the lawn surface. Rake in a loam or sand to allow air to get to the roots. Feed the lawn to strengthen it and able to cope with the moss invaders. Reduce the trees to allow in more light.
Saying all that, moss is great to walk on, stays green in the driest of summers and is home to more creatures than a monoculture of grass. I reckon we should let it live hand in hand with the grass and concentrate on other eseential gardening tasks - like looking at the garden in this gorgeous weather. Don't be a slave to your lawn.

[PhilMcCann]

Dear QSincognitoErgoSum,
Crikey - guess a few tender bedding plants are out then. And I thought our garden at Harlow Carr, Harrogate got it cold in winter!
Plenty of organic matter will warm the soil up - it will act as an insulator as well as providing ' roughage' for your plants. Also, once the plants are in, I would think a thick mulch of homemade compost would act as a duvet in winter. Bamboos can take the cold and one called Pseudosasa japonica might fit the bill. Not fussy about site, withstands minus 20C and grows quickly to 4 metres high. It's a great windbreak and tough as old boots.
Good luck!

[MrsJohnDeere]

Dear Phil,

When should I chop down my lupins? And how much can I take off?
They have finished flowering and have collapsed in a horrible heap, crushing other things around them and looking really messy.

[PhilMcCann]

Dear prettybird,
A computer glitch sent the answer somewhere -so if you got it here are the bones again ( if not, here it is for the first time!)
It's doubtful your peas are suffering from drought as there has been enough moisture under the soil surface for most things to germinate ( look at the weeds!) I reckon we can blame mice - they adore peas and any other juicy seeds ( you mention sunflowers)
I prefer to sow peas indoors, in deep pots on the windowsill and transplant them when a couple of inches tall. Or I put holly branches along the rows outside to deter the mice.
If you want to venture south this weekend all our gardens are holding veg weekends where you will find out everything you ever wanted to know about veg growing:
Harlow Carr: apps.rhs.org.uk/rhseventfinder/details
Hyde Hall: apps.rhs.org.uk/rhseventfinder/details
Rosemoor: apps.rhs.org.uk/rhseventfinder/details
Wisley: www.rhs.org.uk/Gardens/Wisley/What-s-on/Berry-weekend

[PhilMcCann]

Dear kisamama,
Fully understand the need for running about in the garden - both my boys, 13 and 5, live in the garden.
Your trees sound big to move, but anything is possible if you don't mind a gamble. Early winter is a good time to move the trees. Dig a large trench around the trees at a point where you don't find thick roots just below the surface. Then dig down until you reach virtually root free soil. Then cut under the roots ( it sounds hard work and it is!). Your rootball should then be free of the soil - slide a piece of plastic or sacking under the cut and ease the tree and rootball away from the soil. Plant in a new position at the same depth as it was beofre this major surgery.
Then keep it watered, staked and fingers crossed.
Or prune in summer and leave them where they are! I know what I'd do.

[PhilMcCann]

Dear prettybird,
Back again - I've already told you to get to Harlow Carr for the veg weekend!
Lets sort your razzers now: two weeks usually sees it from setting to cropping - but please make sure you net them before you go or the birds will have the lot. Remember: if you don't net 'em, you won't get 'em.
Have a good holiday.