Possible Clues:

• Plant where whistler comes into work
• Plant of the pea family with clover-like leaves
• Ornamental tracery work probed by judge
• Work hard enclosing judge’s leafy plant
• Sort of knot judge has to work round
• Official work clothes for plant
• Whistler painting attributed to Turner at first — that's a bloomer
• Loftier (anag) — clover-like plant
• Plant person on field to get stuck into work
• Three-lobed design