Two summers at Exeter Science Park: SuDS, soil cells and 10,000 plants

YGS delivered the landscape package at the Zeal Hotel, Exeter Science Park just off Junction 29 of the M5 – soft landscape, hard surfacing, fencing and site furniture.

What went in under the trees

Not every tree needed the same treatment, and that is really the point. What goes in under a tree depends on what sits above it.

Trees sit under hard surfacing in the car park, so those needed the full soil cell system – the island of trees that also does the stormwater work there. Others are planted into the rain gardens. The rest are in planting beds, where there is no paving to carry and no need for a load-bearing structure underneath.

For those, that means 120 m² of modular cells at 600mm deep, packed with 138 m³ of good topsoil and sitting on a bed of drainage aggregate. Above them, 135 m² of units that catch surface water and let it soak down through the soil rather than sending it off to a drain.

Two smaller details do a lot of work. Thirty aeration inlets, set flush into the surface so vehicles can drive over them, let air and water down into the soil below. And 120 metres of ribbed root barrier steers the roots away from paving and buried services, so the surfacing stays sound as the trees put on size.

The cells themselves are made from recycled plastic.

Biodiversity planting: what actually went in

Over 10,000 herbaceous plants, ornamental grasses and shrubs were planted across two mixes – one for sun, one for shade – supported by around 1,400 native bare-root hedging plants and just under 1,000 m² of native wildflower seeding.

The ornamental mixes are built for a long nectar season rather than a single display. Early interest comes from Chamaemelum nobile and Fragaria vesca at ground level. Midsummer is carried by Echinacea, Rudbeckia fulgida ‘Goldsturm’, Helenium ‘Moerheim Beauty’, Lavandula angustifolia ‘Munstead’, Salvia officinalis and Perovskia ‘Blue Spire’. Verbena bonariensis runs from midsummer well into autumn and is one of the most reliably productive nectar plants available. Late structure comes from the grasses – Miscanthus, Molinia, Pennisetum, Deschampsia and Calamagrostis x acutiflora ‘Karl Foerster’ – which hold seedheads through winter and provide overwintering habitat for invertebrates if left uncut.

That last point is a maintenance decision as much as a design one. Grasses cut back in October look tidier and support nothing; left standing until late February they carry insects through the cold months. The photographs from this July show them standing.

Then the bulbs – over 7,000 of them, which is what converts a planting scheme into a twelve-month one. Snowdrops open the year. Wild Narcissus pseudonarcissus runs through the meadow and groundcover areas alongside cultivated daffodils. Native bluebell (Hyacinthoides non-scripta) and tulips take spring into May. Then the alliums: over 3,000 across eight varieties.. Allium sphaerocephalon, in particular, is heavily worked by bumblebees.

Planting Mix also carries a run of culinary herbs – chives, rosemary, thyme, sage, oregano, bay, lemon balm and chamomile – with wild strawberry as groundcover. Herbs in flower are among the best pollinator plants in any ornamental scheme.

Hard landscape and site furniture

The package was not planting alone. We laid the patio terrace, installed the balustrade fencing and the green screen panels, and set the planters and benches specified by Space LA. Bug hotels went in through the beds – working with the decision to leave the grasses standing over winter, so shelter and food source sit in the same place rather than one without the other.

Two summers on

We went back at the end of July 2026.

The trees along the entrance approach have made proper crowns and now read as an avenue rather than a row of new stock. The perennial beds have gone over entirely – verbena standing above the grasses, calamagrostis up in seed and holding its shape, echinacea and lavender through the middle. The gravel corridor runs between deep planting on both sides rather than the bare edges it had eighteen months ago. Guests were sitting out on the terrace with the planting up around them.

This is the second growing season since planting. What you are seeing is what the ground preparation, the specification and the aftercare have delivered.

Project team

The hotel was built by RED Construction South West for Zeal Hotels, with the landscape designed by Space LA, our sister company. Space LA designed both the hard and soft landscapes, produced the construction detailing and specified the terrace and garden benches from MMcité. YGS delivered the landscape package on site

Design and delivery under one roof means fewer gaps between what gets drawn and what gets installed – the rooting volumes, soil specifications and species schedule came through to site intact.

If you are procuring a landscape package on a commercial development – hotel, science park, mixed-use or residential – the decisions that matter most are the ones made before anything is planted. Rooting volume, drainage strategy, species selection against maintenance regime, and a realistic aftercare period.

YGS has worked across Devon and Cornwall since 1973 and has been a BALI registered contractor for 45 years. We hold ISO 9001, ISO 14001 and ISO 45001, and are CHAS and SMAS accredited.