The Garden Ghouls series is manned by one single doll that doubles as a playset: Treesa Thornwillow, the star of the Garden of Frights. The doll is 14.5 inches tall, comes with an elaborate stand to emphasize her tree-ness, six charms to populate her branches with, and a mechanism to make the doll grow to about 15.3 inches. The doll became available in Early June of 2017 and a week later also could be purchased in a 4-pack with the three Garden Ghouls - Wings dolls.
The name Garden Ghouls is printed on the boxes.
Garden Ghouls consists of one doll that is integrated with a playset, the first of its kind in the Monster High lineup. Although about two inches shorter, Treesa takes a cue from the size class of dolls founded by Gooliope Jellington. The doll only features unique molds and pieces.
Treesa comes with a short blurb on the back of the box that complements the blurb on the back of the Garden Ghouls - Wings boxes. The "Personal Monstra", "Killer Style", and "Monster Quirk" sections of her profile are also printed on the back.
The line was promoted by means of the Spring Into Action subseries of the stop-motion series and appeared in the last webisode, "The Monster High Ghouls Grow a Garden Party". It does not involve any of the characters being given butterfly wings due to Treesa's pollen as is described on the box, suggesting that Spring Into Action is a replacement for another story.
- The Garden Ghouls - Teeny Critters assortment was to be a complementary line of charms to decorate Treesa with. It went unreleased.