A Japanese couple has taken to social media to share detailed care instructions with the thieves they say stole seven bonsai trees from them — including one tree over 400 years old.

Key points: Thieves reportedly identified the most valuable trees from the couple's Tokyo property, which boasts 3,000 bonsais

Thieves reportedly identified the most valuable trees from the couple's Tokyo property, which boasts 3,000 bonsais One of the couple's stolen trees is reported to be worth about $127,000

One of the couple's stolen trees is reported to be worth about $127,000 The practice of bonsai is considered an art form in Japan

The miniature trees, reportedly taken from a garden in the prefecture of Saitama, north of Tokyo, last month, are collectively worth at least $165,000, according to CNN.

The distraught owners said they were still hopeful their "tree babies" would be returned — but implored the thieves to take proper care of them.

Describing the 400-year-old Shimpaku Juniper bonsai as her "child", Fuyumi Iimura, the wife of the bonsai master who tended to the trees, wrote: "The bonsai [I] raised like my child … are you giving [it] water properly?

"I'm so sad."

Sharing her wish that her bonsais would be returned, she posted: "I would like to raise a bonsai that I will be able to compliment … again."

She told CNN the tree "needs care and can't survive a week without water".

According to CNN, the couple's prized Shimpaku tree — estimated to be worth $127,700 — was slated to appear in a Japanese beauty competition this month.

Ms Iimura told the publication her husband, Seiji Iimura, is a bonsai master whose family practice dates back to 1603.

She explained the 400-year-old stolen tree had been taken from a mountain centuries ago by her husband's family, who shrunk it to its current form of 1 metre tall and around 70 centimetres wide.

"We treated these miniature trees like our children," she said.

"There are no words to describe how we feel. It's like having your limbs lopped off."

Ms Iimura said she suspected the people behind the theft last month were professionals, as they had successfully identified the "most valuable trees" from the couple's property, which boasts around 3,000 bonsais.

She said three miniature pine trees called Goyomatsus were stolen, along with three more Shimpaku Junipers of lesser value than the couple's rare 400-year-old specimen.

The practice of bonsai requires expert care, and is considered an art form in Japan.