Learning from the experts – gardening tips for late May

Visiting RHS Chelsea Flower Show this week has given me ALL SORTS of ideas for this crop of garden tips!  

From how to present your garden plants in their best possible light, to looking after newly-planted trees, there’s plenty to keep us busy…

All tied up

The Show Gardens and the Great Pavilion were stuffed full of plants and blooms displayed to perfection. It would be way beyond sense to aim for such flawlessness in our own gardens, but I expect most of us could help our plants to up their game just a little bit more. This includes making sure that each bloom is held just where the grower needs it to be, but there is quite an art to it.

I know this sounds cheeky, but are you sure you’re tying in your plants correctly?  For starters, don’t put wire around plant-stems, unless it’s only very temporary – it always damages them sooner or later. By all means, use wires in the background for rigidity but secure plants to them using flexi-tie or soft twine. When you’re tying something, run the twine in a complete circle round the cane once before tying it loosely round the stem, which will allow some movement without the twine slipping down. Do the same thing round canes you use to make a network over a clump-forming plant. It will look like you’re playing a very exotic game of garden cat’s cradle, but that’s okay because your gorgeous flowers will soon obscure them.

Be especially careful with clematis stems because they are terribly brittle at their leaf joints. It’s depressingly easy to snap them if you’re doing the job in a rush.

So, gently does it, and if a shoot has attached itself to a plant that it shouldn’t have, it’s sometimes better to cut the stem of the other plant (obviously, within reason!) rather than your pampered clematis princess.

Early clematis

On the subject of clematis, it was refreshing to talk to Katrina on the Raymond Evison stand at Chelsea, who confirmed they prune summer-flowering clematis by cutting them ALL of them down to 6” in early spring!  It did give me a nudge to remind everyone that it’s now time to attend to the early-flowering types though. These are among the great joys of spring – C. cirrhosa, alpina, montana, etc. and as they finish flowering, it’s time to give them a good tidy-up.  

Take out any dead stems and very tangled growth, then trim the whole plant back to a pleasing shape.  There’s no call for brutality here though; all you’re trying to do is to make it look respectable while you’re encouraging some vigorous new stems that will develop next spring’s flowers on the growth that the plant makes this year. So, once you’ve tidied the plant, give it a good watering, perhaps some balanced fertiliser and mulch the roots with something organic.  You are basically saying thank you to it for a job well done this year, in anticipation of it being even better next year.

One exception that I like to make is to leave the old flowers on C. macropetala cultivars like ‘Blue Bird’, because they turn into the most delightfully fluffy seedheads which remain a feature for months.

You need a notebook!

As I wandered around the showground, I noticed all sorts of folk with little notebooks jotting down plant names etc. My sisters tease me about my garden notebooks, but I use mine all the time, and I think I might have convinced Caroline and my son of their huge value (Laura is a tougher nut to crack).

You don’t need anything big or expensive; in fact, if it’s pocket-sized and fairly cheap, it’s better because you’ll use it more if you don’t mind getting it out on a muddy murky day. I recommend getting a hard-backed one so that you can jot things down easily without needing a table.  Then just note down things you’ve planted, and when, and where; To Do lists; plants you’ve seen and where they were; tips you’ve gleaned from anywhere – magazines, the radio, this blog….!  It’s wonderful to look at your notes from time to time – a personal and unique aide-memoire of your gardening journey. Do equip yourself with one right now.

Gardening shorts

• I’ve become a great fan of the companion planting that they were discussing on the Chelsea TV show this week. Whitefly can be a real nuisance in a greenhouse sucking the sap from soft tissue under the leaves and causing plants to distort and wilt. Adult whitefly can each lay hundreds of eggs during the few short weeks of midsummer. I put pots of French marigolds and mint in my greenhouse amongst all my tomato plants, chillies, cucumbers etc. and made sure to brush my hand over them every day to release their scent that these pests loathe – never seen a whitefly in there!

• A greenhouse can get awfully hot quickly at this time of year – make sure shading is in place, keep the ventilation good, and sluice down the floor with water to bring the temperature down.

• This is a good time to take cuttings of cacti, like the attractive Christmas cactus. Leave the cuttings a day or two for the cut end to callous over before inserting them into gritty compost.

• I was really interested in the info on the Avanade Intelligent Garden about the percentage of urban trees that die in their first year (30%.  50% die within 10 years) – their suggestion was to have sensors on the trunks that would tell us what they need to thrive. Not something that will be available to us for a while yet, I don’t think, but it’s a reminder that if you have planted new trees this spring, don’t, whatever you do, forget to water them well at least once a week during the growing season for the first year or two. 
  
  Lack of water is a very common cause of failure in young trees, especially if they are planted in sandy or chalky soils that are much more free-draining than clay ones. A thick mulch of organic matter around the root area can help to retain moisture, as well as keep down competing weeds.

• I adore wallflowers (just look at this week’s feature pic – gorgeous!) but they are just about over now, just as we reach the time to sow more for next year, as well as other biennials like foxgloves. Wallflower seeds are better sown into shallow drills in a spare patch of raked soil because of the long tap root they develop – they should be ready to be transplanted to their flowering positions in the autumn. 
  
  I was very pleased to pick up some delicious-sounding foxglove seeds from The Botanic Nursery stand at Chelsea and will sow these into seed-trays of levelled compost, scatter the very fine seed on the surface (they need light to germinate) and then gently press them down with a tamper. I’ll put the trays in shallow water for 10 minutes, then cover them with a propagator lid (or you can use a sheet of glass) and leave them to germinate in a cold frame (an unheated greenhouse or a sheltered shady spot outside is also fine). they should be up within three weeks or so.

• Raspberries are pretty rampant growers, and they can throw up new canes with wild abandon. Pull or cut some of them out now or you’ll find yourself with a dense thicket of canes which can’t be reached by the sun and air (not the ‘son and heir’ which is a different proposition altogether………..!) – the fruit may be smaller or more prone to disease as a result.

• Aren’t forget-me-nots pretty! And don’t they get EVERYWHERE! Pull them up as they finish flowering, to prevent them dropping their seeds with wild abandon into every corner of your garden.

Chelsea was awash with geums, bringing cheerful colour on almost every stand. Lots of new cultivars but this pick from Louise is still one of the very best and is her Great Plant this Month.

Elaine’s garden is open next weekend for the National Garden Scheme as it has been for the last 24 years. If you fancy a sneak preview of what to expect, click here. Although she assures us that by June 1st, a lot more of the roses will be in full flowering mode, including the ‘King’s Rose’ – the brand new launch by David Austin!

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