Desert ecosystems lack soil moisture, have intense sunlight, and can have hot and cold temperature extremes. Native desert plants adapt to these growing conditions and prosper, filling a niche that provides food or shelter for insects and animals. Disruptions to the natural growing environment in a desert can have long-lasting effects, as the slow growth of most cacti, succulents and arid plants can take decades or generations to recover.
As parts of deserts are urbanized through the introduction of paved roads and suburban houses, the introduction of exotic, non-desert plants occurs along the native desert edges. Although many exotic plant species may prove a supplemental source of flower nectar or cover for wildlife, some plants have an ability to grow fast and invade desert plant communities, becoming know as an invasive species. If a non-native plant reseeds itself and spreads into the adjacent desert, it could out-compete native plants for sunlight, moisture and space. Deserts are a ecosystem that does not naturally endure wildfires, but the infiltration of exotic, invasive weed plants can create an environment full of fuel for fires to proliferate.
The use of non-native plants in gardens creates a growing site in stark contrast to the naturally dry soils and native plants that do not need much soil nutrition. Irrigation to gardens increases soil moisture and application of fertilizers, especially for turf, will drain naturally into desert washes. Such changes can improve survivability of non-native plants in the wild or diminish the health of native desert plants.
Exotic plants also bring new pests and diseases. While a disease or insect egg may be transported in the container of a garden plant, it can soon spread into nearby vegetation areas. If the pest or disease is particularly successful at attacking and harming native desert plants, there is no native, natural mechanism in place to combat it. An introduced pest may act to fully decimate a desert plant community.