THE mother of a botanist missing in Vietnam is to return home after a trip to the region where her son disappeared provided her with "no absolute answers".

Jamie Taggart's mother Jill Mary said the trip gave her insight into how he could have had an accident in the mountainous region and a further search is being considered.

She said: "In the early morning I will be starting my journey home.

"I want to thank all my friends who have encouraged me In my endeavour to find out what happened to my son Jamie 18 months ago.

"Although no absolute answers have been established it has given me insight as to how an accident could have happened.

"His friends in Sa Pa and supporters elsewhere know that it is still feasible that a further search in a different area may bring positive results.

"However this search would have to be planned and undertaken with official permission and the cost worked out first.

"Further enquiries are being made in the villages belonging to the Mung people, seeking evidence that any of Jamie's belongings had been found.

"They are also being asked to inform the authorities if anything comes to light in the future.

"They will be asked if there were other sightings after he was reported missing."

Miss Mary said her son's picture is being circulated in the area, but a suspicion that he could have been arrested for a breach of rules or another reason - which had been brought up at ministerial level - were unfounded.

Neither was there any confirmation that his disappearance was due to foul play, rather than an accident, she added.

The week-long search set up over recent months for Mr Taggart, 42, who was last seen in 2013, involved his friends from a previous visit to the region.

A reward is also offered for information.

The latest search followed a route near Sa Pa after details of Mr Taggart's planned journey were discovered among his belongings.

Mr Taggart, 42, who runs the world-renowned Linn Botanic Gardens at Cove, Argyll and Bute. was seeking to document undiscovered species of orchid and rhododendron.

His mother broke through the red tape restrictions to arrange the new search last week.

The family's ongoing push for information has gained the support of Greens co-convenor Patrick Harvie and then First Minister Alex Salmond who repeatedly pressed for diplomatic intervention.

His mother said funding for the planned search by at least 15 people including food and overnight camping is partly being funded by donations by family and friends and the remainder by the Vietnamese Police Department.

Mr Taggart went missing two days into his trip.

The official search was called off in March last year but Mr Taggart's family and friends have raised thousands of pounds to fund continued searches and local investigations.

Mr Taggart's father, Jim Taggart, one of the most prominent botanists in Scotland who founded the gardens, said last October: "Someone, somewhere must know something."

Friends and neighbours in Cove and Kilcreggan raised thousands of pounds to help the search for him, and actor Hugh Grant, who has close connections to the area, sent a personal note of support to his family.

Jim Taggart bought the Linn Villa in 1971 and set up the famous garden by sourcing plants from China, Peru and the Himalayas.

He only found out his son was missing when he failed to appear on a flight home to Scotland on November 29, 2013.

In an interview at the time he said: "He was on his own but had been in that part of Vietnam two years previously and knew his way around.

"Either something happened on his first day on the hills or there is some explanation we can only guess at."

Mr Taggart, a retained firefighter who is single, took over the gardens in 1997. They feature on Historic Scotland's list of nationally important gardens and designed landscapes.