Sprig is a very excitable, energetic, sweet and adventurous child - qualities that can bring him to adventure and into trouble. Despite acting careless at times, he is utterly loyal to his friends and family, and will ultimately do what is right in the end.
Sprig is an energetic adventurous frog. Although he seems very calm, he is very easily startled.
It is implied in the episodes "Cracking Mrs. Croaker" and "A Caravan Named Desire" that Sprig has somewhat of a need for affection, as in both episodes, once he discovers that someone doesn't like him, he fell into desperation and went to great lengths to make that someone like him.
Sprig Plantar is a 10-year-old anthropomorphic frog of small height. He has hot pink skin with a light pink underbelly and has short orange hair underneath his hat. He has a large, elongated, chartreuse tongue that extends to certain lengths, four-fingered hands and two-toed feet.
As his everyday clothing, he wears a dark forest green hat with olive green goggles and a jade green jacket paired with dark teal shorts.
In "Dating Season", Sprig's head is colored light pink, and he has orange cheeks. He has a yellow beret-beanie-esque hat with blue feathers on his hat next to each other which makes it look like a geyser. Around his neck, he has a big white disc. He has a very short green shirt with big-circle shaped short sleeves. The big-circle shaped short sleeves are peach colored with orange seed shapes on it the short sleeves. He has big-circle shaped pants with thick vertical stripes with the pattern of colors green to yellow. It also looks like the outfit is too big for him.
In "The Shut-In!", Anne creates a human version of Sprig in her imagination named Twig. He is a human of average height with slightly tan skin and reddish-blonde hair. He wears a dark green beanie with pink and brown pins. He possesses a similar school sweater to Anne with a green undershirt and a dark green jacket over it as well as dark blue shorts, white socks and black sneakers. To complete it, he has a red backpack.
- Fiddle and violin: He is very good at playing the fiddle and the violin. It is implied that he has perfect pitch to go along with it.
- Singing: He is a good singer and can sing while playing his fiddle.
- Vocal mimicry: He has a talent to perfectly imitate other voices.
- Slingshot: He uses this for playing and self-defense. He also demonstrates having a great aim with it.
Not much is known about Sprig's past expect he and his sister Polly were taken under their grandfather Hop Pop’s wing after their parents were eaten by Herons and he is childhood friends with Ivy Sundew.
From the start of the series, Sprig starts off as being considered something of a strange kid in the town of Wartwood. Over the course of the first season however, this begins to change through the influence of Anne Boonchuy while also changing her perspective as well. Along with the rest of the Plantars, they slowly begin to gain some respect from the town with many people looking at Sprig as the "fun Plantar".
One of the story arcs in season one involves Sprig's personal relationships. In "Hop Luck", he ends up getting engaged to Maddie Flour, albeit forcibly by Anne in an effort to get dough. Later on in "Dating Season", Sprig is revealed to be friends with Ivy Sundew, an old acquaintance. At the end of the episode, Sprig suddenly realizes that he is in love with Ivy and makes it his goal, through the encouragement of Anne, to admit his feelings to her. While Maddie makes spare appearances, Sprig still brings her up in a resigned manner. While he likes her, he considers her too weird and creepy. It is not until the episode "Cursed!" when he finally breaks up with her and learns that despite her weirdness, she simply wants to be friends with him, and he accepts her. In "Anne of the Year", he and Ivy are finally able to admit their feelings for one another.
Sprig also spends numerous amounts of time learning from his mistakes and maturing somewhat. In "Sprig Vs. Hop Pop", he learns to be more accepting of rules and in "Trip to the Archives", he realizes that even though he would rather have fun, he should be more concerned with helping Anne with her problems instead.
In season 2, Sprig joins his family and Anne in their journey to Newtopia, in hopes of finding a way to transport Anne back into her world. In the episode "Handy Anne", it is revealed that he has several different slingshots, and briefly goes on a crisis to select which one to take to Newtopia, but eventually manages to settle down in which one to use.
They eventually arrive to Newtopia in "Marcy at the Gates", where they meet Anne's other human friend, Marcy Wu. In spite of Marcy being clearly harmless, Sprig is initially suspicious about her, fearing she might be like Sasha. As the group helps Marcy to deal with Barbari-Ants that cause Newtopia to be closed for protection, Sprig constantly watches over Marcy, expecting her to betray them at any minute. However, he soon realizes Marcy is a friend when she saves him from the Barbari-Ant Queen.
In "Hopping Mall", Sprig helps Anne with finding the perfect gift for her mother, putting them in conflict with Priscilla the Killa over a butterfly teapot, but Anne eventually relents when she learns Priscilla wanted it because it belonged to her own mother. That night, as Anne tells Sprig about her mother, Sprig reveals that his and Polly's mother died when they were young. Therefore he says that he can't remember how she looked or how her voice sounded, briefly causing him to somberly wonder if he can miss her even througth he never knew her, before receiving a hug from Anne and letting his emotions take over him.
In season 3, Sprig alongside Anne and rest of the Planter family are transported to Earth were they must search for a way home.
- Early in development, Sprig was going to be named Weed.
- Sprig claims that he has a short attention span. This, combined with his excitable personality, implies that he has Attention Deficit Hyperactivity Disorder (ADHD). When asked if this was the case with his character, Matt Braly said it is "very likely" he has ADHD.
- In "Family Shrub", his eyes are revealed to be blue.
- Sprig is apparently based on the strawberry poison-dart frog. While they occasionally look pink, they are usually orange-red in color, similar to Hop Pop. However, they also usually possess dark blue arms and legs.
- He considers Anne "way too old" for him when they were accused of being a couple, implying that he prefers dating people closer to his age.
- Sprig seems to be a musical prodigy as he can sing and is capable of performing the fiddle flawlessly.
- Sprig, arguably, has already had two love interests. Ivy Sundew, whom he starts dating at the end of season one, and Maddie Flour, whom he was engaged to, but broke off.
- As revealed in the concept art, Sprig went through numerous color changes before settling on hot pink.
- From time to time, the bottoms of Sprig's webbed feet are colored dark pink as if they are dirty.
- According to Anne in "Contagi-Anne", Sprig likes mushrooms.
- His surname means "to plant" in Portuguese.
- It is revealed in "After the Rain" that Sprig and Polly's parents died after getting devoured by large herons. While not stated, it is implied that he remembers this as when Hop Pop began to feel depressed from thinking it, Sprig tells him that it was not his fault.
- In "Sprig's Birthday", it is revealed that Sprig's hat was a birthday gift from his parents.