Category Archives: Horticultural advice

Advice for August about Dahlias

How to grow Dahlias

If you want late summer colour choose dahlias. Enjoy different flower forms, from bouncy looking pompons to exotic waterlily styles, and a kaleidoscope of colours to fit every palette.
Dahlias are stalwarts, working hard in borders, pots or as a cut flower crop. Although they flower from June to late October, they are well known for the August / September period. I think they bridge the gap between blowsy summer planting and robust autumn colours. They bring zing to a border so I use a variety of them to introduce a bit of drama in different planting combinations.

Dahlia 'Sunny Boy' showing August colour in the walled garden.

Dahlia ‘Sunny Boy’ showing August colour in the walled garden.

Maintenance is easy. Dahlias enjoy the sun and like a rich, easy draining soil. They have tubers, like potatoes, so feed them well as you will be feeding for next year too. Slugs love them, so you will need to protect them. If you choose tall varieties stake well and early as stems snap easily in the wind.

Consider foliage colour, which varies from light greens to deep purple, giving opportunities to under-plant with exciting combinations. For example, we’ve married orange (pictured) on bright green stems with purples and golds from verbena and heleniums for a blaze of colour.
Grow dahlias from seed, plant tubers or take cuttings in late spring. A packet of seeds will give you dahlias for years.

They die right back at the first frost and you’ll lose them over winter in wet ground or sub-zero temperatures. It’s a good idea to lift them in late autumn after the first frost when the stems flop. You can risk leaving them in the ground with a good mulch to protect them – as long as you are confident of predicting a dry winter that’s not too cold. And if you can do that, come and see me for a job as the garden weather forecaster!

Nick Haworth, Head Gardener

How to create a wild flower meadow

National Meadows Day – Advice from the Head Gardener

As July 2 is National Meadows Day, this month’s advice is to help you make a meadow. Whether you have a few feet or a few acres, the principle is the same and wildlife will benefit. The pleasure of seeing the right plants in a natural environment, providing colour and movement from spring until late summer can be achieved just by fiddling about with the right patch of scruffy lawn.

If you have been to see the garden lately you will know the meadow is full of orchids and butterflies. In spite of the cold start and the damp June, the weather has been really good for wild flowers.

Wild flowers in the meadow at The Garden House, under the silver birch trees

Soil conditions and aspect

You’ll need poor soil and lots of light; an open position is ideal, for sun all day and plenty of weather.  Buy seed, not plants.  But no grass seed; grass will find your meadow anyhow and it bullies wild flowers, so if you’re seeding a grassed area, include Yellow Rattle. It’s a pretty little parasitic plant that reduces the vigour of grass. Avoid annuals, (cornflowers, poppies etc.) because they need regularly disturbed soil. Depending on the size of your meadow, you might need a few packets or to buy seed mix by weight.

Prepare the ground by removing everything, or cutting grass as low as you can and raking great ugly patches into it. Seed wants to touch soil. Sow the seed as per instructions.  It’s a good idea to add sand to the seed mix so you’ll see where you throw it and be able to spread it more evenly.

Maintenance for your meadow

Mow (or scythe or strim) just once in late summer and leave the hay in heaps to drop seed before clearing it. Don’t feed or fertilise, but keep the soil poor and the grass miserable. Meadows aren’t high maintenance; they just need the right maintenance. In future years you can augment your meadow with plug plants and bulbs. Plants will naturalise if happy. Our meadow now has too many orchids to count, they’ve been hybridising at a rate of knots. Visit soon before they go over and get down low to appreciate them close-up. It’s glorious.

Nick Haworth, Head Gardener

PS. To find out more about National Meadows Day, read here at the Magnificent Meadows website.

National Meadows Day Walk

Learn about our wonderful wild flower meadow

Take part in a guided walk this Saturday July 2nd, with Donna Cox, of the Moor Meadows community initiative. It’s a local group that is working hard to increase and celebrate the meadow lands of Dartmoor, so we’re very happy to have Donna on site to help visitors understand the workings of ours. The weather is forecast to be better in the afternoon than the morning, so you should be enjoying a walk through the meadow in the sunshine.

The Garden House meadow is one of many throughout the country that will be featured in this national event. We encourage you to come along and take the opportunity to learn about planting, ecosystems and maintenance from an expert.

This year the Dactylorhiza, or marsh orchids are looking better than ever. We have an innumerable  mix of pure and hybrid species, so if you an orchid enthusiast this walk will give you the opportunity to see what we’ve got…

Purple orchid close up showing spotted leaves

An orchid in the wild flower meadow

The guided walk is free for all garden visitors, usual gate fees apply, Friends of The Garden House free admission. There is no need to book but please be prompt as it will start at 2.30pm.

The cottage garden’s gardener

Visitors who linger in the cottage garden may have come across a gardener,hard at work, often hidden behind a large hat. Hazel Ward has been taking care of the cottage garden since the very first day that weeds were cleared from the site.

Flowers fill the shot and a lady stands in the background

Hazel Ward at work in the cottage garden.

Here is Hazel’s description of how the cottage garden grows…

“The plan was for a naturalistic planting of both wild and cultivated flowers around the walls, which would then blend seamlessly into the wild flower meadow behind it. Self-seeding was always encouraged but this has always meant a lot of weeding out of the more vigorous wild flowers such as Campion and Ox eye daisies.

As the perennials have established there has became less open space for annuals such as field poppies to thrive I have got round this by sowing them in pots and then clearing spaces for them and then transplanting them in the spring. Over the years I have added other native annuals such as corn marigold, cornflower and corn cockle to the mix.

I have always loved the naturalistic style of planting and have been happy to leave wild flowers amongst cultivated plants especially as they attract such a lot of butterflies and insects.”

It’s a pleasure to be working and the view is magnificent

“If members of the public don’t like the cottage garden they never tell me but plenty of visitors do tell me that it is their favourite part of the garden and they like it because it looks so natural and unmanicured , often that they are trying to create a more natural area and a wildflower meadow in their own garden at home. In the summer it is a pleasure to be working in the cottage with the bonus when you look up the view is magnificent. I have become very attached to it as a garden over the years which is why I still come back a day a week to work in it although I now live the other side of Launceston.”

This year, as in every other, the cottage garden is an orchestrated riot of colour and variety. It’s down to Hazel’s eye for detail, her skill and the passion she still has for this single spot of land.


June advice from the Head Gardener

How to grow Eryngium

It’s fitting that as I write this Chelsea Flower Show is in full swing. Every year it seems a trendy plant is “discovered” at Chelsea, and Eryngium was just that about a decade ago. In spite of looking exotic it’s a native plant that has been with us for centuries. You may know it as “sea holly.”

The Eryngium has earned its place where form and colour are important, and does well if it gets full sun in excellent drainage. Bees love it. As an umbellifer it has a long tap root so it doesn’t enjoy being moved. There are many varieties with different heights and flower forms, but it’s fair to say they are generally blue, spikey and love the sun.
Although it’s got no scent to write home about bees love it so the blue we like must look good in ultra-violet too.

The plants in the photo are a hybrid that is very blue and about 50cm high. The blue colour gets brighter the more sun the plant has. This isn’t a plant for a shady corner so we have ours in a well-drained, walled garden. We use the colour to as a foil to lead the eye into a long border with sumptuous dark wine colours, bright blues and hot reds. You can see the tower in the background so if you are familiar with the Garden House you’ll know where the borders are!

This plant is a hard worker and if you can keep it warm and well-drained it will even seed around. Let the seed grow where it lands (it’ll be the following spring) and then move the young plants before they get too established.

In spite of the cold start to the season the garden is leaping on now and it’s a pleasure to work in it every day. Next month I might put pen to paper to give advice about wildflower meadows as I think it is going to be an extraordinary year for them.

Advice for May from the head gardener

How to grow Pulsatilla vulgaris

This bright little rock plant is one to reach out and touch. The leaves and seedheads are so silky smooth and feathery you can barely feel them. Better yet, when the light catches them from behind they almost have a halo glow.  The flowers can be upright or nod around on the end of the very slender stems. They are plants for gravel gardens and very well drained soil. They’re no more than 30cm high – usually about 20cm, so we’ve hundreds of them planted on hummocks and slopes in our quarry garden so we don’t have to bend too far down to appreciate them close-up.  A slope helps with drainage too and lets you see them backlit when the sun is out.

Close up of a single pinky mauve flower with a yellow centre.

Pulsatilla vulgaris is perfect for gravel gardens

Perfect flowers for a well drained site  – see them in our quarry garden

They’ve a reputation for being in flower at Easter and a common name of Pasque (passion) flower to go with this Easter link. Mind you, with the cold start and the early Easter this year ours were nowhere to be seen and they’re a bit later this year than normal. They’ll flower for a good 4 – 6 weeks though so they earn their place. The colour range runs from a very deep red wine through violet, lilac and pinker shades to a white.  I don’t think any are garish colours, there’s something soft and sophisticated about them.

They are best grown from winter root cuttings, or by potting on self-sown seedlings. Bear in mind they take a while to establish a long tap root and mature plants hate to be disturbed. Put them where you want them rather than mess them about.  Once established they will give you years of enjoyment.”

Man in grey jumper admiring a Magnolia Felix 'Jury'

Nick Haworth, Head Gardener