Over the past 10 years there has been a significant change in the role of electricity in horticulture. From being largely an aid to the amateur gardener, rarely used by the commercial grower, electricity now plays a substantial part in modern commercial horticulture. Some of the earlier expectations, based chiefly on the small-scale work, have not developed as expected and hoped.In situsoil warming, for instance, has not taken its expected place in commercial horticulture, and large-scale glasshouse installations are few and far between. On the other hand, the use of soil-warming equipment to provide bottom heat for propagation in frames and propagating cases has increased substantially. Direct space heating by electricity was hardly expected to play any significant part in commercial glasshouse work, but through electrical auxiliaries alone has it been possible to develop various modern methods of large-scale automatic heating using either coal or oil. Where the circumstances and scale of requirement do justify direct electrical space heating, emphasis is placed on the need for correct design, particularly in relation to a proper basic temperature. Probably the most prominent role of electricity in commercial horticulture has been in the provision of artificial lighting for plant growing in various ways; increase of plant development and its control have both been successfully applied through the use of electric light in ways and with means which are commercially successful. The development of new wiring methods and equipment has aided the provision of safe wiring installations in horticultural premises.