This game is sweet.
The pixel art and the animations are all great. Especially the game page. Very nice. The sun animation is very cute. I don't like the dithering in the grass. None of the other sprites use dithering so it stands out (but I just hate dithering in general so maybe it's just me). I would have preferred little patches of tall grass to differentiate the dark and light grass areas. I think texturing the grass slightly would have looked great (google "pixel art grass" and that's what I mean by texture). Or some extras like tiny 1-4 pixel wild flowers; tiny so they aren't confused with the flowers you grow. Something subtle so you don't lose the worms or your plants in the background.
Enemies are simple, but having them spawn in bursts is a great way to do it. If they just spawned 1 every ~2 seconds, it would be much too easy to keep them under control by killing them one at a time. The burst ups the intensity of the game for a bit and you have to figure out which worms to hit first. The scythe stunning them was key to the strategy of killing them. And the scythe doing a bit of area damage meant you always wanted to try to hit as many worms as you could which added a lot of fun second-to-second decisions trying to perfectly aim your clicks. The slight cooldown on the attack means you can multitask a little early on. You need to attack some worms far away, then while the cd is resetting, multitask by spending that time filling up with water. Then going and finishing off the worms when the cd is ready.
I kinda had no idea what I was doing a lot of the time. Not that it made it any less fun. The game was easy enough to figure out what you had to do in a broad sense even if you didn't know the specifics. Like I knew I needed to water plants and slice worms. I figured out that I could hover over the water at the bottom to refill my can without being told, because that's pretty clear. But I was unsure what watering plants did when they were in their final stage. I guess it keeps them alive, but I wasn't sure if I needed to fill up the blue bar to get to another stage. How does the chopping your own plants thing work? Sometimes it wouldn't work, sometimes I'd get 2-4 new plants. Does the plant need to be in the final stage to be able to be cut? I'm not really sure why I would want multiple plants. Do I get more points? They sort of act as lives. If I have multiple plants, the worms need to kill them all for me to lose, but they don't spread very far so the worms can kill nearby plants pretty easily. I didn't really know what the upgrades did. It seemed the upgraded scythe lowered the cooldown which was handy. I see now that the game page has the upgrade info.
All in all, the game is really fun to play. It has great flow between chill watering and stressful scythering. And this is your first game? What a great game to start with.