Weekend Work: Time to throw away chemical fertiliser

What to do

Throw away your packets of chemical (inorganic) fertiliser and vow to do without them this year – at least everywhere except pots where plants can't be expected to survive on the measly ration of compost they have to grow in.

High levels of inorganic fertiliser in the soil can suppress the growth of beneficial mycorrhizal fungi. Research has shown that many plants have a complicated symbiotic relationship with these fungi, which may protect them from disease. Arbuscular mycorrhizal fungi (AMF) provide an effective defence against Phytophthora, which causes devastating damage in gardens.

Get more information on mycorrhiza from PlantWorks Ltd, 1/19 Innovation Buildings, Sittingbourne Research Centre, Sittingbourne, Kent ME9 8HL, 01795 411527, plantworksuk.co.uk.

What to see

Today is your last chance to see Forest, an installation designed by landscape architect Deborah Nagan, which for the past eight weeks has been part of the Emma Cons garden, opposite the Old Vic theatre in London. Ms Nagan hopes that her work will make people "question their usage of resources and their responsibility for the world's forests". So why was the forest composed entirely of cypress, and why were all the trees shipped in from Italy?