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New plants find it hard to get established in gaps since the ground is full of roots and neighbouring plants have first call on water and nutrients, besides creating heavy shade. There is also the chance the ground might be infested with honey fungus which will inhibit growth.

What might work better is to push in a series of stakes in the gaps nine inches apart, allow the privet plants on either side to produce long side shoots, then weave them in to fill the gap.

Or put a piece of trellis into the gap, supported by a stout post at each side; clip the privet to shape round each section of trellis to accentuate it, and if you want denser cover, grow ivy on the trellis. Choose one with a contrasting curly or arrowhead leaf shape or, if it’s in a place that gets plenty of light, go for a gold, variegated ivy.