Although plants are the "diagnostic” elements of landscape gardening, neither theory nor practice pay sufficient attention to the care after them. Too often we meet with vegetation elements in bad state. Causes are the mistakes in proposals, realization and system of care after vegetation elements; change of the required function; change of site conditions; abiotic, biotic and anthropic destructions, as well as high age. The most important solutions are: relevant legislation, principles included in the Firenze Charter,specificity of plants as alive composition elements, significance from the viewpoint of care after historical monuments, legitimate interests of other branches, present demands of people on their use in landscape architecture and economic power of society and their relation to monuments. The restoration of vegetation elements, especially of trees is the most topical and most complex activity of landscape and garden formation.