The 30-year-old crowned a supreme individual performance with an excellent free-kick in the second half, while the Light Blues also had goalscoring contributions from Charlie Devlin, Leah Eddie, Rio Hardy, Kirsty Howat and Liv McLoughlin.
The triumph sets up a last four showdown for Rangers in the competition, with attention now shifting to next Sunday’s Old Firm clash in the SWPL in Hamilton.
Jo Potter made two changes to her side from last weekend’s resounding triumph over Montrose, introducing Vic Esson between the posts alongside Brogan Hay on the flanks.
And almost immediately the Light Blues had Motherwell on the ropes, breaking the deadlock with a quick free-kick from Wilkinson found Eddie at the far post who slotted her finish beyond the goalkeeper to mark a first goal in Gers colours.
Potter’s side certainly had the bit between their teeth and they doubled their advantage moments later to leave the home side with it all to do.
A delivery from the right-hand side was initially met by Wilkinson who stabbed a pass back to Devlin lurking 12 yards from the goal, with the English midfielder firing a powerful finish under Rebecca Cameron in the Motherwell goal.
Rangers were rampant and two quickly became three when Wilkinson – who else? – cannoned a thunderous effort off the underside of the crossbar and Hardy, as all good strikers do, was positioned perfectly to nod the ball into an empty net.
Motherwell were offered a lifeline shortly after when they pounced on a lapse of concentration in the Rangers ranks and Amy Sharkey fired a sharp finish into the top corner.
Indeed, Wilkinson’s link-up play was the talk of the stands, and it wasn’t long until she got into the goalscoring act when she nodded an unstoppable header into the bottom corner from a pinpoint delivery from Nicola Docherty’s cross.
Those hoping for the Light Blues to relent were to be left short-changed as they added a fifth before the half-time interval when Hardy’s low strike was spilled and the summer arrival from Southampton reacted first to bundle the ball over the goalline.
The Gers emerged for the second half and, with the game essentially secured, it took a while for Rangers to click back into gear.
However, a sixth goal arrived with 20 minutes remaining and it was a third of the evening for the irrepressible Wilkinson.
The 30-year-old assumed free-kick duties at the edge of the penalty area and her delicious clipped effort nicked off the underside of the crossbar and over the goalline to continue her relentless goalscoring form this campaign.
There was still time for Liv McLoughlin to etch her name onto the scoresheet when the energetic midfielder reacted first to a delivery from substitute Lizzie Arnot after an initial flick-on at the near post.
The scoring wasn’t finished there, however, as Kirsty Howat found time to make an impact off the substitutes bench, stabbing home from close-range after a clever pull-back from Hardy.
MOTHERWELL: Cameron, Penman (Barclay, 73), Watson, Addie, Ronald (Gibb, 55), Collins, Rice, Sharkey, Boyes, McGoldrick, McCartney
RANGERS: Esson, Docherty (Hill, 45), Eddie, Middag (Arnot, 45), Hay (McAulay, 78), Devlin (Howat, 60), Hardy, Maclean, McLoughlin, McLeary, Wilkinson (Lafaix, 73)
Subs not used: Fife, Rafferty, Ross, Austin