What shall I plant in the 4m² soil area in front of a London house? I want something beautiful and that needs minimal care. Also it shouldn't grow taller than 1m. The house is located South-East from the spot, so the area receives little sunshine, except during summer afternoons.
Many, many more. Do a search for 'shade garden' and look for plants that will grow in your hardiness zone.
Living in London myself, I'm wondering what length and width the soil space is in your front garden, rather than the overall square metre size. Also whether it has a low wall running along the front of it which blocks light as well.
That said, and assuming you don't want to spend hours in the front garden doing maintenance, I'd choose a mix of mostly shrubs, particularly evergreens, some ground cover and a few perennials/bulbs.
Smaller shrubs which do well in shady situations are:- Sarcococca varieties; Mahonia aquifolium; Prunus 'Otto Luyken'; Leucothoe*; Skimmia (note you will need a male and female for berries, unless you choose the variety S. 'reevesiana'*); *Pieris 'Katsuro'; Buxus; Acer (japanese varieties, particularly the slow growing dissectum ones). Note that Acer does not like alkaline conditions, but is fine on neutral soil, and also does not like windy situations nor hot sun around midday in summer. If there is some sun at times, Euonymus fortunei varieties will also do reasonably well. All plants mentioned are evergreen, barring Acer. Plants with * require acid soil conditions.
Evergreen ground cover: Lamium maculatum (White Nancy, Beacon Silver); Ajuga reptans; Campanula portenschlagiana (syn. muralis); Bergenia; primrose/primula/polyanthus. Perennials: Dicentra formosa; Astilbe; Pulmonaria; Rogersia; Digitalis (foxglove); Tiarella; Campanula persicifolia; hardy Geraniums (Cranesbill, not Pelargoniums) such as 'Wargrave's Pink'.
Bulbs/corms: Crocosmia Lucifer; Daffodil (choose miniature varieties, less fading foliage lying about for the required six weeks after flowering), Convallaria, hardy Cyclamen varieties.