Most plants need a root system to grow and thrive, as roots perform essential functions such as absorbing water and nutrients from the soil, anchoring the plant in place, and storing energy. However, there are some exceptions and specialized scenarios where plants can grow without a traditional root system:

1. Hydroponics: In hydroponic systems, plants grow without soil. Instead, their roots are submerged in a nutrient-rich water solution. While the plants still have roots, they are not in soil but rather in a controlled liquid environment.

2. Epiphytes: Plants like orchids and bromeliads are epiphytes and grow on other plants or surfaces without rooting into soil. Their roots may absorb moisture and nutrients from the air or rain but are not anchored in the ground.

3. Tissue Culture: In plant tissue culture, small plant fragments or cells can grow into complete plants in a nutrient-rich, sterile medium. These plants develop roots later in the process when transferred to a suitable growing environment.

4. Vegetative Propagation: Some plants can grow from cuttings or other plant parts that are not initially rooted. For example, certain types of cuttings can develop roots once placed in a growth medium or water.

In general, while plants can adapt to different environments and growing conditions, having a root system is crucial for most plants’ long-term survival and health.