Some well known perennial vegetables from the temperate regions of the world include asparagus, artichoke and rhubarb.

It continues to be tended by student volunteers, and produces a variety of annual and perennial vegetables and flowers.

And asparagus is especially easy to grow, partly because it is among the few perennial vegetables.

Generally speaking, perennial vegetables tend to be more beautiful than annuals - or rather, we allow them to be.

Forest gardening is a fully plant-based organic food production system based on woodland ecosystems, incorporating fruit and nut trees, shrubs, herbs, vines and perennial vegetables.

However, he also observed that a small bed of perennial vegetables and herbs he had planted was looking after itself with little or no intervention.

A 'herbaceous layer' of perennial vegetables and herbs.

However, a small bed of perennial vegetables and herbs he planted was looking after itself with little intervention.

'Herbaceous layer' of perennial vegetables and herbs.

Hart favoured shade tolerant perennial vegetables.