Conservation of plants refers to preservation, repair or restoration of plant population on the earth.
Plants are easily destroyed by strong wind currents, due to improper nutrition from soil and also heavy pollution.
They generally have tendency for long life but due to above factors, their life span is drastically reduced.
Besides these natural interruption for their healthy life, human activity like excess deforestation, excess use of manures and pollution creates problems of conservation of plants.
Plants are of most importance for in-habitation of man on earth so their conservation is inevitable for future.
Tips for conservation of plants:

Limit the pollution: Pollution by radiation, water or soil pollution can be toxic to plants and may decline their life span. So precaution to minimize the pollution has to be taken up to conserve plants.
Safe guard from cattle: Many new plants are planted besides road now and then. But they are destroyed even before they grow up due to cattle. So cover the plants to minimize damage by cattle.
Minimal use of furniture: Big trees are chopped off for making furniture. The demand is high due to rise in construction of new homes. The breakdown of huge trees is easier but the time taken for their huge growth is vast. Even big trees are helpful in triggering the rainfall and also maintain atmospheric moisture level. So cutting down bug trees has more disadvantages.
Minimize deforestation: Deforestation is full fledged in some countries due to growth of cities, town and also requirement to occupy agricultural or forest land for industrial purposes. This greatly hinder natural greenery as many plants are cut down in the process. Further the chances of natural climate in the locality is altered.
Encourage plantation: Excess and mass level plantation has to be encouraged to rise the plant population in all the cities and also remote areas where ever possible.
Also read: Facts about plants