His comments come in the wake of the Gardening Which? revelations that consumers were being short changed by carrot and beetroot plugs at £1.09 each.
Coumbe said: "Plug plants offer an excellent starting point for those who are new to growing their own — and offer particularly good value if you're looking to grow plants like celery and tomatoes. But the best options of all for those looking to make the most of their budgets are perennials, especially plants like asparagus and fruits such as blueberry and strawberry.
"If pennies count, those are the best to plant to get a high yield in terms of crops and coppers."
The £1.09 plugs from Gardening Direct have since been withdrawn.
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