Circle of The Seedling

Druids of the Circle of the Seedling delve more completely into
the ancient rituals and hidden knowledge of plant magic. These
druids meet together in their Plant Wild Shape, sharing their
wisdom and arcane secrets with each other in Druidic, while
appearing to just be a small bunch of shrubs and trees. As a
member of this circle, your magic allows you to be one with your
surroundings, gaining intricate control over the plants around you.

Plantspeaker

Also at 2nd level, when you are transformed into a plant creature
you gain the ability to command nearby mundane plants. As an
action, you can turn difficult terrain caused by plant growth into
ordinary terrain in a 5 foot radius centered on you, or you can turn
ordinary terrain where plants are present into difficult terrain in a
5 foot radius centered on you. After a 10 minute duration, the
plants return to their original condition.
Additionally, while you are transformed into a plant creature
you ignore difficult terrain caused by plants.

Leaf and Branch

Starting at 2nd level, you can use your Wild Shape feature to take on the shape of plants. These plant shapes have the same maximum CR, and limitations as beast shapes. Inanimate Plants are considered CR 0

Take Root

Starting at 6th level, you gain the ability to root yourself in the
ground while in your normal form, forming a protective armor of
bark around yourself. As an action on your turn, you can root
yourself in the ground, reducing your speed to 0 and granting you
advantage on checks made to avoid being moved.
Until you end this effect by using your bonus action or fall
unconscious, you have resistance to slashing, bludgeoning and
piercing damage from non-magical weapons.

Green Heart

Starting at 10th level, you are immune to poison damage, and the poisoned condition. When you take a short rest within direct sunlight you may add your wisdom modifier to each hit die you use to determine hit points regained and you regain a spell slot of a level equivalent to the number of hit dice you spent.

One with Nature

Starting at 14th level, you gain the ability to cast barkskin and
speak with plants at will, without expending a spell slot or
material components.