The high-profile Bright Sparks project will see the bank replanted with a "stunning array" of Chinese windmill palms, red hot pokers and golden, purple and red grasses, transforming the view and helping enhance the Eden Project's identity as a contemporary global garden.
An acre of ground opposite the Core education centre has been cleared in preparation for the mass planting.
With the site's famous biomes as a backdrop, 20 towering Chinese windmill palms were planted yesterday (5 April) by a team of Eden's outdoor horticulturists, with more plants due to be put in the ground in the coming days.
Gordon Seabright, managing director of the Eden Project, said: "This is a really exciting moment for our garden – the biggest new planting scheme for 15 years. This part of the outdoor gardens has evolved from a backwater into one of our most high-profile areas. It is adjacent to the busy Core, viewed from the Core café terrace and our bridge.
"The plan for this slope is to electrify it with colour and form, to make it horticulturally special for our visitors and as an educational resource for our apprentices and new higher education students."
The latest figures from the Association of Leading Visitor Attractions show Eden Project visitor numbers climbed 11 per cent last year to 960,000. Seabright has attributed much of the improvement to an ongoing programme of investment in horticulture.
Speaking about the current scheme, Seabright continued: "We have added greatly to our collection of windmill palms (Trachycarpus fortunei) that thrive on this slope and, among them, will showcase flowing grasses and vibrant perennials from the southern hemisphere, particularly South Africa, in the 'new naturalism' style.
"This will include what we hope will be the start of a nationally significant collection of kniphofia – better known as red hot pokers.
"We are calling the new initiative Bright Sparks because of the forms and colours of the planting as well as the involvement of our own 'bright sparks' - our young horticulture apprentices. Re-planting this large slope is a major project and will require a huge team effort."
When the slope was originally planted, it was the backdrop to a temporary food and education camp and showcased a mix of grasses. Over time, the whole area became dominated by invasive phalaris grass which is now being cleared.
Eden's aim is that the kniphofia planting will eventually be deemed a National Collection, which would be a first for the project. The plan is to plant around 2000 kniphofia of around 100 species and cultivars, some of which are rare or specialist and have been bought with help from the Stanley Smith (UK) Horticultural Trust.
Seabright said: "I believe that by securing National Collection status we can raise our stature as a garden. We are very much a contemporary botanical garden and we aim to broaden our appeal among informed and expert gardeners.
"By having a diverse range of kniphofia we can have an extended flowering season and show the beautiful diversity they offer. We also have the nearby South Africa area within our Mediterranean Biome to display some of the tender varieties, enabling us to show a more comprehensive collection."