The Supreme Personality of Godhead, Śrī Hari, is the master of all living entities, including all the prajāpatis, such as Lord Brahmā. Because He is the all-pervading and indestructible master, He has created all these trees and vegetables as eatables for other living entities.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
अहो प्रजापतिपतिर्भगवान् हरिरव्ययः । वनस्पतीनोषधीश्च ससर्जोर्जमिषं विभुः
aho prajāpatipatirbhagavān hariravyayaḥ | vanaspatīnoṣadhīśca sasarjorjamiṣaṃ vibhuḥ
SB 6.4.8