A healthy garden will support several species of ladybird. 

Ladybirds are beetles in the family Coccinellidae, they range in size from 1 to 10mm and are round or oval. Ladybird larvae all have a similar elongate body shape with three pairs of obvious legs, most are black or dark grey, some have yellow or orange markings and many have hairs or spikes. Adults of the most familiar species have brightly coloured (red or yellow) wing cases (elytra) with dark or light spots.

There are more than 40 species of ladybird considered as resident in Britain, about 20 of these are small (<3 mm) and dark in colour and so often not recognised as ladybirds.

Many ladybirds are predatory feeding on aphids and, scale insects, they can help keep these insects under control. Other species feed on mildews and a few feed on plants but none cause serious problems in gardens. The UK ladybird survey provides more information on ladybirds and facilitates recording.

Harlequin ladybird, Harmonia axyridis. An introduced species that became established in Britain in 2004, it is now one of the most commonly seen ladybirds. Adults are 8-10mm in length, and very variable in colour and markings, two common forms are black with two red spots or orange with 18 black spots. Larvae reach up to about 10mm in length and are characterised by having two orange stripes and being spikey. This species feeds on aphids and other insects, occasionally becoming cannibalistic. There is some evidence that it has caused declines in some native ladybirds due competition for food. It is however, not desirable nor necessary to attempt to control this insect, it is easily confused with some native species and is largely a predator of aphids.

Two spot ladybird, Adalia 2-punctata. Adults are 4-5 mm in length and very variable in colour, common colour forms include red with two back spots and black with two red spots. The larva is dark grey with some orange markings. This species is widespread and often found in gardens feeding on aphids. It is sometimes available from biological control suppliers.

Seven spot ladybird, Coccinella 7-punctata. Adults are 5-8 mm in length and almost always red with seven black spots. The larva is grey with four pairs of orange markings. A widespread species often found in gardens feeding on aphids.

Eyed ladybird, Anatis ocellata. The largest UK ladybird reaching 8.5mm in length, usually red with 14 black spots, which are often circled in yellow. The larvae is grey and spikey with some orange markings. A predatory species usually associated with conifers. 

Cream spot ladybird, Calvia 14-guttata. A brown ladybird with 14 cream spots, 4-5 mm in length. Larvae are grey with two pale markings. Usually found on deciduous trees feeding on aphids and plant suckers (psyllids).

Orange ladybird, Halyzia 16-guttata. Adults are orange with 12 to 16 white spots reaching 6mm in length. Larvae are yellow/cream with black spots. Usually found on deciduous trees feeding on mildews.

Kidney spot ladybird, Chilocorus renipustulatus. Adults are 4-5mm long, black with two red kidney shaped markings. Larvae are dark and very spikey. Usually found on trees and in gardens often found on Euonymus feeding on euonymus scale.

Twenty-two spot ladybird, Psyllobora 22-punctata. A 3-4mm long yellow ladybird with 20 to 22 spots. Larvae are yellow with black markings. Feeds on mildews on a wide variety of plants.

Bryony ladybird, Henosepilachna argus. First recorded in the UK in 1997 this brown ladybird with 11 black spots is vegetarian feeding on white bryony (Bryonia dioica), although it has not become a problem on this plant. Adults are 5-7 mm long and the larvae are usually pale yellow with black spikes.

Fourteen spot ladybird, Propylea 14-punctata. A 3-5mm yellow ladybird with a pattern of 4 to 14 black markings. The larvae are grey with white markings. Feeds primarily on aphids but will also eat other insects such as scales.
 
Several other species of ladybird may be fund in gardens, descriptions of all UK species can be found at the UK ladybird survey.

Most ladybird adults overwinter in sheltered places often in large groups. These overwintering sites can include inside buildings and the harlequin ladybird can be present in very large numbers.

In spring the adults emerge and disperse, mate and lay eggs. Predatory species lay eggs on plants with colonies of aphids or other insects, those that feed on fungi on mildew affected plants. Many species can have several generations during the summer.