Episode 8 Gardeners' World

-WHISTLES

-Nige?

Hello. Welcome to Gardeners' World.

This is the moment in spring when we go from all the subtle,

gentle colours, the primroses and the lemons of early spring,

which are so beautiful in their own way,

to an explosion of colour which comes from the tulips.

It's as though the season just hits a conveyor belt and off we go.

Today, I will be continuing trying to rectify the tragedy

of my blight-stricken box

by planting a different kind of hedge...

..and Rachel gets an exclusive look behind the scenes of one

of the best alpine collections in the world...

-Oh, wow, John! This is amazing!

-It's quite impressive, isn't it?

Not just all of that colour, it's the fragrance as well.

..while Carol is in Devon, meeting a man who has devoted

himself to the glories of the erythronium.

These are special plants.

All year, I wait for them to come up in the spring.

If there's one plant that I would never want to be without,

it is the erythroniums.

I've kept these alpines under cover all winter,

not to protect them from the cold at all -

they're as tough as old boots, but from the rain.

They have very special conditions.

They like really good drainage, they can withstand any

amount of cold, any amount of heat, but they just hate very wet winters.

And you can see that they look good in terracotta.

I love the delicacy,

the way that each pot creates its own little garden.

There's very little to do to look after them.

Once you've planted them, they're almost trouble free.

What you do need to do at this time of year is just check them

over, see if there are any dead pieces that need taking off,

if the grit has washed off in the rain, perhaps, to replace it,

and that's it.

You can, of course, make new plants from the sempervivums.

Here, where it's very crowded,

each one of these will make a new plant,

so if I just pull off a rosette like that

and just gently tease it out, there it comes.

I could pot that up, it's got roots on it, and that would quickly make

a new plant and you can see that's one that was potted up last autumn.

Now, of course, these are very common familiar types,

they can take the hardship of an English summer and winter, but there

are many different types of alpines, some of which need specialist care.

And Rachel has been to the Royal Botanic Garden in Edinburgh

to see the huge collection of alpines.

Alpines may be tiny, but when it comes to adding colour

and interest to your garden, they can certainly punch above their weight.

I grew to love alpines when I was a child

because my father had a passion for them

and most weekends, we went to the local garden centre

and would come back with these little child-sized pots of perfection,

which we then planted in our rockery.

That was wonderful, I have to say, but it was nothing like this -

the Rock Garden at Edinburgh Botanic Garden.

This is home to more than 5,000 plants

and it's just the tip of the iceberg.

In their natural home, above the tree line,

alpines withstand extreme weather conditions, such as snow, ice,

gale force winds and fierce sunshine. They're small, but mighty.

But the one thing many of them really don't like is winter wet,

so in the UK, some species can be difficult to grow unprotected.

These alpine houses have been built specifically to accommodate

the plants which can't easily live outdoors.

John Mitchell heads up the alpine team.

He's travelled the globe collecting wild specimens

for their ever-evolving collection.

-Oh, wow, John! This is amazing!

-It's quite impressive, isn't it?

It's really impressive.

The other thing is when you come in, it's not just all that colour,

it's the fragrance as well.

The scent is overpowering and it's usually from these narcissus.

You get this very sweet scent coming across.

Absolutely beautiful, and one forgets how many small bulbs

come into that sort of overall alpine umbrella.

Yes, we have the narcissus, we have muscari. We have tulips.

Just now, the alpine house is at its best,

and the display is absolutely spectacular.

-Lovely primulas there at the end, as well.

-The allionii are spectacular.

They always flower really well with us in Edinburgh.

So, roughly how many plants do you think are in here?

There's about 200 plants in here, but what we do is,

every Friday, we bring plants from the back area that are

in flower into here so the public have something different to see.

Behind the scenes we have about four or five thousand.

So I'm going to get an exclusive look at those?

You are, yes. But before we do that, we need to maybe take some

-of these plants into the back to replace them.

-Right.

Oh, look in here. SHE GASPS

This is our new bulb house.

These are your understudies waiting for their moment in the spotlight?

Anything in flower here then gets moved to the front house

if we've got space, so they all get their minute of fame.

Tell me about the plants you've got in here.

Where have you actually got them from?

This one here, the Fritillaria imperialis,

-we collected this in 2005 in Iran.

-It's absolutely beautiful.

And those leaves are really glossy, too.

The leaves are lovely, this lovely dark stem,

with the red flowers hanging quite tight to it is quite unusual.

But an absolutely beautiful plant.

So where else have your plant-hunting travels taken you to?

I'm mainly concentrating in Central Asia, Tajikistan, Kyrgyzstan.

We've done work in the Russian Altai,

and we're going to try to get to Kazakhstan at some point as well.

Because that term "alpine" suggests that they are

-all European in origin, and of course they come from...

-All over the world.

Where has it come from, this obvious love of alpines?

I think I have to blame my father,

because he was a student here way back in the '60s,

and then moved to St Andrews to build the botanic garden there.

So from an early age,

I was brought up in botanic gardens as my playground, and then I got

the chance to come here 30-odd years ago, and I've never looked back.

-I absolutely love the place.

-They won't let you go now, you know.

-Hopefully not!

-I've seen bulbs. You've whetted my appetite.

-What else is there?

-The other house I shall show you straightaway.

Now, this is like an alpine creche, all these tiny plants.

This is where when plants,

we take the cuttings and they've established,

they come in here, and then we can grow them on, keep an eye on them.

Once they get bigger, we move them to another house.

And you grow them in the sand because?

The sand keeps the roots moist in the summertime,

and you can see everything in here is in clay pots,

so the clay pot is porous, keep the sand moist,

the moisture goes into the clay pot and keeps the roots moist.

Presumably there are alpines that are very rare to find in the wild.

Is that something that you're looking for in a botanic garden,

to help save those plants?

A botanic gardener is always looking for rare

and unusual plants for conservation.

Here we have Dionysia afghanica,

which just grows in certain parts of Afghanistan.

This plant is probably very endangered in the wild.

We also have this plant here, which is Hepatica falconeri,

which was only known in Pakistan.

And then in 2012, it was found in Kyrgyzstan.

We managed to get permission to collect it, and now

here it is growing in Edinburgh so we can do research on it.

How exciting.

I feel so privileged that I have been able to see

some of these rare plants.

I know they flower fleetingly, and they are small,

but how can you not love alpines?

I totally agree.

My interest in alpines has only developed very recently,

and it's as though I've suddenly realised how jewel-like they are.

They are fantastic.

So I must go back to Edinburgh, any excuse to go there is fantastic,

and see the collection that they've got.

But they're very easy to grow at home,

and I've got a nice old stone trough here, perfect for growing them in.

If you can get hold of a trough, use it.

If you can't, you can use a sink,

any container as long as it's not plastic.

Stone or terracotta is ideal because it's porous,

so you don't get water collecting.

Make sure there is a drainage hole, and make sure it's raised up

so the water can actually run away rather than just sit underneath it.

Put a crock over the hole so it doesn't get clogged up and blocked.

And mix up a really, really gritty compost.

I've got here a peat-free general-purpose compost

mixed in equal volume with grit. Don't cheat on this.

If anything, add more grit.

That's the crucial thing, drainage.

Now, I've got a selection of plants here.

And there are so many alpines to choose from, and they're cheap.

You can buy plants like this extraordinary

gypsophila from Pakistan for a couple of quid.

Now, I'm going to just put two or three together.

We've got a little Androsace here, these flowers growing up

almost like a little tiny primulas, which comes from Asia.

And then, from the mountains of central Spain, an Armeria.

Little pincushion foliage,

and these beautiful little pink flowers that appear above it.

And they'll be happy blasted by icy winds,

as long as they have light and aren't too wet.

This sedum which I've grown last year in a separate pot,

I'd like to pot on into here.

What I'm trying to get is glaucous greys and pinks mixing in.

These plants are all sun-lovers,

so you position the trough in maximum sunshine, facing south.

This...

actually is a saxifrage, cotyledon,

which will flower with white flowers in summer,

keeping our pink and white themes.

Now, you can see I've spaced it out, nothing crowding in on each other.

We can always add. You've got room for them to grow.

And then I'm going to dress this with grit,

partly because it guarantees better drainage,

and also because it ties it all in together. It looks better.

As long as you've got really good drainage, watering them

won't harm them at all, and it's necessary to water plants in.

It settles them into the compost.

But they don't need much attention at all.

As long as they've got the drainage and the sunshine,

they'll look after themselves.

And of course, you can have alpines in the very smallest of gardens,

and they look good in a big garden.

Every garden should have them.

Now, Carol is continuing her journey round Britain

looking at the plants that have shaped our gardens, and meeting

the people who have devoted themselves to caring for them.

This time, she's gone to Devon to meet Keith Wiley,

who has a superb collection of erythroniums.

With their gentle, charming flowers set amongst handsome,

marbled leaves, few plants give as much pleasure as the erythronium.

For me, these exquisite little flowers really epitomise

the whole soul, the spirit of spring.

But for all their beauty and refinement,

you very seldom see erythroniums

grown in gardens.

It's as though people assume

that something that looks

so special must be difficult to grow.

But one man in particular has spent many, many years of his life

getting to know these plants intimately.

For much of his life, Keith Wiley has been captivated by them.

His work has expanded what this genus can offer all our UK gardens.

Have you always been in love with these plants?

-I certainly have.

-What is it about them that you love so much?

I think it's partly the fact that they are actually

only there in the spring. They are just so beautiful.

I have never seen an ugly erythronium.

To me, they are the epitome of grace.

And each individual flower is like a sort of Chinese pagoda.

It's a beautiful shape.

There are a few Eurasian species,

but the majority of them are American?

I think there's about 30 species, and probably three quarters of them

grow over on the Pacific Northwest of America.

And how did you feel the first time you saw them growing in the wild?

It was almost a religious moment for me

when I saw erythroniums for the first time. Very, very special.

I suppose that actually seeing them

growing in the wild must inspire you to try different things yourself.

Without doubt.

There was one occasion where I came round in southern Oregon

and saw a whole mountainside.

There were some growing underneath the shrubs,

and the colour of the flowers was a perfect combination with

the fading flowers above, and I took the same principle.

It happens here, look.

You can see these erythroniums here,

they're all in their various shades of pink,

and they're matched by the pink and white of the magnolia above.

-What species is this?

-This one's Erythronium revolutum.

What kind of conditions do they need?

They want the same conditions as hostas or primroses.

-Woodsy kind of soil.

-Exactly that, yes.

Moisture retentive, but reasonably well drained, but not waterlogged.

Look at that. That's exquisite.

The way that most species proliferate is by seed.

That's the way they do it in the wild.

I planted here at the top of the slope

so that it would seed down the slope, and colonise this little bank here.

If you look carefully, you can see tiny baby seedlings. How exciting!

Just like little blades of grass. So easy to weed out.

And some of them have still got their little seed pods on the top.

So when you come across these plants in the wild,

are there are lots of natural hybrids between them?

No, they don't really naturally hybridise,

because they grow at such widely spaced distances.

They grow 50 or 60 miles apart, so they have got no chance,

-unless you've got long-distance bees.

-They don't fly that far!

30, 40 years ago, there was only five or six species in our gardens.

And then in the last 30 years, lots more species have come in,

and the bees have had a chance to actually do their business,

and we've got lots of different hybrids starting to arrive.

The big difference between species and hybrids is that species basically

will come from seed, whereas a hybrid, you have to divide them.

And what are the sort of qualities you go for?

I think the real beauty about hybrids is their flower power.

They can make big, solid batches of colour.

This one here right in front of me is one I named after my sister, Jenny.

It produces a lovely, quite late in the season patch of this lovely

pink, with these really...

inside this really quite delicate markings.

It's one of the real beauties of erythroniums,

-the beauty of turning their faces up.

-How many have you grown?

I've probably named 15 or 20 so far,

and we are trialling another 100 or so to see.

People are going to be so enamoured of this plant now they've

seen it growing in your garden.

But how do you get hold of erythroniums?

They are not the most common things, are they,

in garden centres and nurseries?

They're not really lending themselves to mass production,

so perhaps more realistically

the best way is to order them from specialist

or reputable firms who will send them, lift them at the right time,

pack them in the right way and send them off to you at the correct time.

-Which is what, August, September?

-Probably sometime in late summer,

right through into very early autumn.

If there's one plant that I would want to grow

and would never want to be without it is the erythroniums.

All year I wait for them to come up in the spring.

They are so special and on a day like this, what could be better, really?

-Yes. It was obviously meant to be, wasn't it?

-It was.

Obviously, Keith's erythroniums are extraordinary,

but I find even just having a few here and in the garden

transforms it.

Erythroniums have a mixture of genuine exotica, but also

a kind of easy elegance that almost no other plant can provide.

A month or so ago, we began the process of taking out box hedges

that had been afflicted by box blight.

This was a major change to the garden,

and the box blight is still present.

It's killed back great lengths of hedge

and we may well have to take it all out.

But for the moment we are stopping where we are.

I can't put box back in because the fungal spores that cause

the blight can remain in the soil for five or even more years.

So what I'm going to do is plant a yew hedge.

Now, yew, that's Taxus baccata,

is normally used in a garden as a big backdrop.

But what I want to do is grow it as a low hedge.

So this is a fairly new development on how to use yew.

It doesn't matter whether you want to grow a 20-foot yew hedge

or a three-foot one, or any hedge.

There are certain things you need to do to prepare it.

This has had the roots of the old hedge taken out

and it's been dug over thoroughly and grit added.

It is important when you're preparing a hedge

to get a nice wide, clean area. Don't just dig one spade's width.

Clear the ground, if need be, a metre wide.

There's plenty of room in the soil for this to grow into.

Yew needs good drainage and it hates sitting in wet, cold soil.

So on our fairly heavy soil in this wet part of the country,

we always add grit for any kind of tree or shrubby planting.

But particularly for yew,

if your soil is wet and cold, you must add drainage.

The next step is to make sure it's straight.

Get or make a line, which is simply string attached to sticks,

set it back from the edge of the path or the border,

because any hedge will grow wide however much you cut it.

Rule of thumb, you need to allow about three foot width for it.

I've made myself a measuring stick.

Plant that along there.

If we put the first one just a little way from the edge, like that,

and plant along...

I'm going to put these at 18-inch centres.

If that looks frighteningly far apart, stick with it.

These plants will grow nice and strong

and very quickly meet to join a hedge.

Also, yew is quite expensive. These were a fiver each.

Plant them with enough room for the roots to develop

and you'll get a much healthier, stronger hedge.

So that's plenty close enough.

Tell you what, I'm going to take some clothes off.

Don't be tempted to plant in a saucer

or, in terms of a hedge, a groove. Because the water will collect.

If anything, plant them on a ridge.

In fact, the soil here mounds up above ground level.

So that, in effect, is a ridge.

But if in doubt, mound the soil up

and make sure the roots are never sitting in wet, cold water.

Yew takes the first year to establish,.

so I wouldn't expect any significant growth on these in 2014,

but next spring, next May, June,

they will really start to put on new growth.

Most of that initially will be upwards,

but they will start to thicken out, and you just keep sides

this way trimmed and that will encourage lateral growth.

And they will meet and join up in about the second or third year.

And I would expect this to be a hedge

that I can top off at three foot,

because we won't cut the top until it reaches its ultimate height,

after four or five years, because yew grows about six inches a year.

Even though I said that yew hates sitting in water,

that doesn't mean to say that they don't NEED water. They do.

They need watering once a month, a really good soak once a month,

unless it doesn't rain and if it doesn't rain for a week, water them.

You do this for the first summer.

Take it through to October,

and thereafter they can look after themselves.

When I've watered them thoroughly,

they must be mulched to keep the moisture in and keep the weeds down.

You may not be planting hedges this weekend,

but here are some other things you can be getting on with.

If you're raising your sweet peas from seed

and they are now growing strongly, like these,

which I sowed in March, it's time to pinch out the growing tips.

This will encourage a bushier plant.

And then when you plant it out next month, will give you

more flowers throughout the growing season.

At this time of year, herbaceous perennials are growing very fast,

and this makes them vulnerable to damage from any bad weather.

So it's important to stake them before they need it.

I like to use home-made wire supports, but twine and canes

or prunings from shrubs will do the job just as well.

Whatever you use, gently support and prop the plant up so it looks

as natural as possible

without lashing them into a harsh straitjacket.

Courgettes are one of my favourite summer vegetables

and now is the time to sow them.

I use small pots and sow two seeds per pot

and will weed out one of them if they both germinate.

Put them somewhere warm, water them and leave them to grow.

If the weather stays cold, you may have to pot them on again.

But don't plant them out until the nights have warmed up

and then they will grow strongly.

I don't think I've ever known such a good year

for purple sprouting broccoli, which is a treat -

so much nicer than the great clumpy broccoli at you buy or get served.

The delicacy of purple sprouting broccoli.

And it's going to seed really fast.

There's still another couple of pickings,

but any warm weather and it's just shooting into flower.

So those will come out over the next week

and be followed in rotation by root crops - carrots, parsnips -

and there's space here and I want to put some parsnips in there.

Loosen the soil, rake it over so it's a reasonable tilth.

And then don't tread on the soil if you can help it.

Now, I just use the side of my hand to make a furrow.

Just run down either side...

Now, the seeds are flat...

and quite a good size, but they are very light,

so it's easy to get too many in together.

A decent sized parsnip wants to be spaced three or four inches apart.

And there are two ways to do this.

Either sow them as thinly as you can

and then thin them more later,

or sow two or three seeds

in little clumps about four inches apart.

Parsnips are slow to germinate. This can mean you lose some.

You get weeds growing up. You don't know where to weed

because there's no sign of the parsnips

for up to about five weeks.

So what I do is sow radish in the same drill,

and the radish germinate very quickly,

in a couple of weeks at most.

And they are ready to eat after about four weeks.

So from four to eight weeks, you harvest the radish,

by which time the parsnips have germinated and started to grow.

Clear the last of the radish away

and you have a line of parsnips in their wake.

Neither affects the other's growth rate,

but you use the space to twice the effect.

And also, apart from anything else, it just marks the row.

So, I've got Cherry Belle here.

Sprinkle the radish in...

I'll fit another couple of rows of parsnip

and radish in this little plot.

But that's all we've got time for this week.

And we're not here next week because there's snooker on instead.

However, we will be with you in a fortnight's time at Malvern,

at the RHS Malvern Spring Festival.

So, I'll see you there in two weeks.

Till then, bye-bye.