This is the 4594th most frequent Russian word.
грядками
"Грядками" means "garden beds" or "planting beds" in English.
Here, 'грядками' refers to the plural instrumental form of 'грядка', meaning 'garden beds'.
Мы посадили овощи на грядках в саду.
We planted vegetables in the garden beds.
In this sentence, 'грядками' is again the instrumental plural form, indicating the means by which something is achieved (i.e., using garden beds).
Грядками можно выделить участок для посадки зелени.
Garden beds can be used to designate an area for planting greenery.
Here, 'грядками' indicates the objects of attention, using the plural instrumental form to discuss actions involving the garden beds.