The first thing you see at the O3’s summer show is a huge nest. The man-sized bundle of dried leaves and grass rests matter-of-factly on the exhibition floor, both strange and familiar. Created by Emma Kwan, the ‘Nurture’ installation piece is interwoven with dried medicinal herbs and tea leaves so that it becomes at once natural and artificial: a nest that might have fallen out of an enormous tree, and a concoction of man-made ingredients.

This playing with the ways humans relate to nature is typical of the whole exhibition: its subjects vary from a vast, uncultivated forest in Bee Bartlett’s ‘Boars Hill Tree Canopy 2’ to the neatest bunch of cut roses in the painting ‘Flowers and Coffee’ by Roberta Tetzner. The exhibition’s curation brings out the contrasts between these different representations, so that we are frequently surprised by unsettling, unexpected combinations of ideas. The Tetzner painting, for instance, is hung next to ‘Stolen Rose’ – a figurative etching by Morna Rhys of red blooms on a white background. This clarifies its counterpart so that the layered circles of red and pink hues become symbols for roses too, and we see the same object interpreted in both geometric and organic ways.

Elsewhere Rachel Owen’s screenprint ‘Noah’s Eye View’ depicts a single, enormous white flower spread across the upper half of a stark black background. Its majesty is subverted when we realize it is a blow up of an image of a dandelion, and that the impression of natural grandeur which might be expected in a sweeping landscape by Constable have been given instead to a common weed. We are forced to re-examine the way we consider not only nature but the way it is represented.

In another corner, Sarah Simblet’s ink drawing ‘Lime Tree (Tilia)’ is hung by Rachel Ducker’s wire sculpture ‘Three People Tree’. Seen alone, the Simblet drawing has a softness brought out by the featherlike detailing on the finest branches — but  the tight prickliness of Ducker’s wire construction brings out a sharper, more imposing side to Simblet’s carefully wrought ink lines.

Finally, you descend the gallery stairs to Lisa Busby’s ‘Moth’s Wings’, another highly intricate expression of man-made and natural worlds colliding. An old wardrobe seems to explode with plant life, its vine-covered wallpaper blending into a huge pile of dried leaves and the stems of potted flowers that loosely surround it. Piles of books, record covers, picture frames and tapestries that cover the floor. The main part of Busby’s practice is musical composition, and throughout the exhibition her songs can be heard playing from a laptop on a rickety desk nestled among the leaves. The whole installation is organic to the extent that Busby herself ‘lives’ inside it and constantly adds to it, hanging knitted flowers on the stalks of real flowers and proffering trays of cake to visitors. At one point I looked down at ‘Moth’s Wings’ from the upper gallery and saw just Busby’s feet as she lay down within the plants. It seemed another of this exhibition’s emblems of merging natural and cultivated worlds.