While working on restoring an Elizabethan garden, Rosemary witnesses the owner's cousin commit suicide only to later see him alive and well at an open-air market.
A famous columnist is murdered while Rosemary and Laura rid a hotel's vineyard of pestering weeds. Strapped for cash with no land-rover, the gardeners pull out all the stops in an attempt to kill the weeds without breaking their backs.
Laura is distressed to hear that Rosemary was shot dead while working at Engleton Park; but finds a very lively corpse at the home Rosemary's mother. Bodies, motives, suspects and clues pile up around an archaeological mystery.
Rosemary and Laura work on re-planting the historic Regent's Park garden, filled with its colorful flowers and an array of permanent visitors. But hidden amongst these frequenters of the park are many secrets soon to be revealed, all mysteriously connected to a three-legged dog.
When the rich widow hiring Rosemary and Thyme to restore a garden and waterfall is murdered, a gardening book written by her late husband may hold the key to the solution.
Quinnie Dorell, hostess of a TV gardening show, fills in for Rosemary, who is sidelined with a broken leg, in solving the murder of an investigative reporter.
The house of a respected, long-dead botanist becomes sought after because it's believed to contain seeds of a now-extinct plant that may offer a cure for malaria.
While creating a memorial garden and helping to solve a murder, Laura tries to repair her relationship with her estranged daughter following her divorce.
An old flame of Rosemary's, a noted scholar of Spanish Islamic history, contracts with the girls to help him restore an old Moorish garden on his estate in Spain but murder and suicide prove to be distractions.