Dan Pearson's top 5 garden plants for early summer | Designer plant picks for May + June

We're in the first week of May here at Hillside and in the last 10 days the garden has just exploded and we've gone through all these small blossom seasons and right now we're in the middle of the hawthorn blossom season and the garden is beginning to really get going. Mostly greens, first colours coming through in terms of flower and this wonderful feeling of bridging of spring in very early summer. This is Peony Imodii late windflower, a selection of the species which is found in the Himalayas and through to Afghanistan growing on south-facing slopes in clearings on the edge of woodland so it really likes to have sort of cool around it but some sunshine during the day and I think it's always worth knowing where plants come from when you're placing them in the garden. And this is one of my favourite species, Peonies. It is absolutely spectacular from the moment it emerges out of the ground in March with leaves that are bronzed and burnished and shiny and they expand quite quickly over those first couple of weeks until you suddenly find that it's grown into something that is about a metre tall and as much across. I've got about four or five plants stretching through the top part of this garden where they're connected to the hedge at the back of the garden so that they've got that cool in the morning and they were divided maybe five years ago. They're very long-lived, they're something which if you find the right position for it will be very happy in hearty ground with plenty of retentive moisture in that ground for many many years and they don't need division. I simply wanted to divide them to get more because it's such a beautiful thing that it works in multiples. This is Euphorbia serraticarpa from southern Italy and Sicily and it's one of my absolute favourites. Where it grows in the wild it's on open south-facing slopes, lots of sunshine, rubbly ground, free drainage and that's where it really likes to be in the garden where I've got it growing in more hearty heavy loam that we've got here. It tends to peter out quite quickly, falls over, it grows too fast. Where it starts to self-sow and here it's growing in a little yard by one of our outbuildings where we've got rubbly ground and very free drainage. It grows a much stronger, healthier, heartier plant and one of the great things about this plant is it starts flowering in March, continues right the way through to December so it's got an incredibly long season of these bright lime green flowers which are also wonderful for pollinators and I use this as a contrast plant. Reds are wonderful against it, most colours work with it and as I say it's always got this wonderful fresh feeling. It's a terrific plant. The only downside is that it's toxic if it's eaten and if you break the leaves when you're working alongside it the sap can burn your skin so you do have to be careful when you're around it but it's a top 10 for me. This is the giant fennel Ferula communis and it occurs in the southern Mediterranean through into the Middle East and when I've seen it growing down there it's always growing in rubbly dry places on south-facing slopes with really good drainage and that's what it likes here so we've always got it where the water falls away from it in the winter. Some people say it's monocarpic i.e. after it blooms it dies but these ones have been living here for many years. Their seed originally given to me by Fergus Garrett from Great Dixter where he's got many different forms of this now and it actually takes about three years to flower from seed and we've had these in here probably five years and they're still going strong and they're starting to seed now in the garden finding places where they like to be always the dry places with the good drainage and I'm starting to see some variability now between the forms that we've got here some with more blue leaves some with more green leaves they're the most spectacular thing they start growing in November with would be winter rains in the southern Europe of course so the winter green here they have this fantastic ferny foliage throughout the winter and then in March they send up this great big bolt of energy which turns into this flowering spike which is not edible in fact the if you touch it and get the sunshine some people are very allergic to the touch of this plant so it's something I tried to keep not very much on the edge of the border but somewhere just a little bit inside so it doesn't isn't something you bump into and one of the wonderful things about the plant is its bolt upright movement as these inflorescences come up in the first part of the summer it's very fast movement out of the leaves and then up to well over two meters and the Romans used to use these as measuring rods ferrules because they're very light and they've got these wonderful divisions between each of the leaf axils and it dies back very quickly after it flowers so about the end of June the leaves start falling away but you're left with these wonderful seed heads which then go on right the way throughout the winter and this year I've started to leave some from last year so you've got the comparison of old seed heads and the new goes side by side to make it feel more naturalistic. All the roses in the garden here at Hillside have got a wild feeling about them and they're often very closely connected to their species parents and this is Rosa spinosissima single cherry and it's a selection of our native scotch briar which is usually cream and grows in sand dune environments near the sea it's immensely hardy and can deal with a lot of exposure and dry ground and hard living and this plant here which is a pink selection is also incredibly tough it's growing here at the side of the barn growing in ground which I haven't really put much energy or preparation into because I knew it would feel right on the edge of what we call the barn garden which is planted directly into rubble around the barn so it's not highly nutritious ground at all and because this has got a little bit of shelter it's grown up into the native honeysuckle which grows alongside it and is twice as tall as it usually should be which is about a meter meter 20. It's a wonderful thing even though it only blooms once and I think one of the great things about it is that you really have to focus on a plant that only blooms once in a different way than if it was recurrent and it has a tremendous perfume I'm standing now in this cloud of sweet rose lemony scented perfume and then it goes on to produce dark hips which festoon these long arching branches for the duration of the autumn so it has many seasons this lovely delightful ferny foliage these beautiful little pink buds that open into these quite bright sericea flowers and then berries later in the season it's tremendously tough it doesn't need any sprays of any sort and it sits here very well in this naturalistic setting. This is our native scotch briar rose spina cisterna and I collected this one from seed in sand dunes on the gower in southern Wales and the seed comes in the form of these wonderful black hips which hang on right away into the autumn and then there are these beautiful little creamy dog roses that start to appear now in May. They have a fairly short season but they're really beautiful for the time that they're out and I love this plant it's completely tough as old boots will survive in a wide range of different conditions and different soils and is gently running and if it really likes you it can be a problem it can form thickets um but here it's sort of self-contained where I put it on the edge of the lovely drive This is tulipa sprengerei which is the latest flowering of all the species tulips it's earlier this year but it can go into June and it's very particular for being happy in a little bit of shade and with slightly more moist ground than most usual tulips. It comes from the Pontic coast in Turkey where it's nearly extinct I think but it's used quite freely now in gardens it's extremely long-lived if you decide it likes you it'll be there for many many years but it's just about finding that right niche for it. So I've been growing some from seed every year I take some seed and grow 20 or so nine centimeter plants where I've always got a stock of them and I move them into places where I think they're going to start to naturalize. In my old garden in Peckham I just hit gold straight away and put it somewhere and it started to seed and within no time at all I had flowering plants three or four years later and it was starting to carpet an area under some willows that I planted there and it likes this sort of slightly shady half-light place where there's deciduous growth above it and so it can get early light before the leaves come on the things above and then it goes completely dormant during the summer and it has these absolutely wonderful flowers which have a greeny reverse and then these scarlet centers with yellow anthers and then it goes on to produce very beautiful bolt upright seed heads which stay on for the first part of summer and then get consumed by all this foliage. If you're lucky you can get it established in short grass in the right position I've not managed that one yet but it's so happy to.