When lighting a single pleached tree a single 36° beam spotlight is usually the light of choice, positioned close to the trunk about

50cm-100cm with the light pointing straight up.   See Fig1

Suggested light fittings: Compact Spike Spot, Spike 3,5 & 8, P8R & Cygnet

 

When lighting a row of pleached trees use wider 60° beam spotlights positioned midway between the trees and pointing

straight up.  See Fig2 below

Tip:  Due to the neat nature usually associated with pleached trees try using recessed lights for this type of installation or even hide spiked fittings in amongst the planting.