Short answer:

• Sadharan vanaspati means “common plant life” (vanaspati) that, in Jainism, is considered to host many souls in one body (anant-kāy). These are typically root-related plant beings like tubers, bulbs, and underground parts.
• Because uprooting or cutting these plants harms countless tiny beings, Jains often avoid eating them. This is a key reason many avoid underground vegetables (kand-mūl) in their diet. Both Śvetāmbara and Digambara traditions generally uphold this, though exact lists can vary by local practice.

What it means in simple terms:

• Sadharan vanaspati = root and underground plant foods (potatoes, onions, garlic, carrots, etc.) that are avoided to minimize harm to many living beings.
• Above-ground vegetables and fruits are preferred when possible.

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