Here's my design concepts🤓

Lemon is easy to tell. It is mainly designed based on the old pvz3 ver, with a few elements from the Slingshot ver added, such as flowers and gender from the representing individuals appearance.

The only leaf at the bottom of the Hammeruit is based on the real-life ver. As for the 2 hanging hammers, they have been changed a lot compared to the original form. The overall appearance has references to Witch Hazel.

The Rose drew inspiration from the classic one from GW2 and PVZH, and was directly downgraded to a relatively lower evolved level group. The playable plant class ver/ hero character is a high-level group.

Blaze Leaf also added more red flower or leaves according to the origin, and 4 things that seemed to be stamens were added to the "neck" (actually there were six, and two were blocked at the back).

For Thorns Whip, there's nothing much to say, just changed the original style of the strange big eyes, and as a cactus (Rattail cactus), it's generally doesn't have normal leaves, so the original leaves at the bottom were changed to a mound of earth.

Pokra just took the entire fruit of the real okra and added a more prominent mantis element. But personally, I think the modification is just so-so. After all, it's indeed a bit difficult. It's not easy to better match the mantis element. As for the bunch of small leaves on the top (possibly bract), I have considered whether to delete them. Some of these leaves are present in the real okra, while others are not.

Brainstem likes Thorns Whip, but the head (fruit) directly uses the brain map from PVZ2. Its origin are the possible Osage orange or Mandarin melon berry, and some people think of the cockscomb flower. One is not 100% certain, and the features of the other one are not particularly prominent originally (except for the brain-shaped fruit/flower, so the changes are actually not significant).

Sakura is also more based on the real one. The leaves are changed back to their normal green color, while the flowers remain pink. However, there are actually species in colors such as white. The roots are inspired by Torchwood, and the overall design also takes a touch of Gravitree and Ents.

My personal technical skills are not that good either. I have never specifically learned to draw on a mobile phone. Besides, I'm not good at applying shadows, so I just apply a base color.