Flowers are by far the most common item in natural kei prints, crochet details, and accessories. They often appear in bouquets, baskets, or wreaths, but it's usually just all-over flowers.
✽Fruit✽
Cherries and strawberries are seen quite often, just as in Lolita fashion, although grapes, peaches, pears, and even pineapples also make appearances.
✽Baskets✽
The flowers and fruits are often displayed in wicker baskets for a bit of extra country charm.
✽Clover✽
Four-leaf clovers are good luck after all, so why not wear them everywhere?
✽Teddy Bears✽
These little guys are everywhere in natural kei. They appear in the form of prints, crochet accessories, embroidery, actual teddy bears, and even these inexplicable bear garters currently available from Pink House.
✽Bunnies✽
Similar to the teddy bears, plush bunnies (and regular bunnies) are a common theme that pop up often. It's no surprise that natural kei fans also have an affinity for BtSSB's Usakumya.
✽Generally Cute Critters✽
Cats, dogs, ducks, squirrels, and any other cute animals can appear in prints. Kaneko Isao once did a kangaroo print, although the cuteness is debatable. This summer Pink House released a print with mermaid cats called "Mew-maids".
✽Hats✽
They're not just for your head, you can wear hat prints on your clothes too!
✽Ribbons✽
Ribbons and bows are a common design detail in natural kei, and they're also on prints because why not.
✽Sweets✽
Foods like cake and ice cream make appearances, although they're not as common in natural kei as they are in lolita fashion.
✽Kewpie✽
I don't have a good explanation for this one, but Kewpie dolls seem appear on Pink House items quite a bit. I'm not sure what the obsession with them is.
✽Holidays✽
Get in on the Christmas or Halloween spirit when that time of the year rolls around! Santa, Christmas trees, and wreaths are common in the December.
✽Ugly Sweaters✽
That is just about the ugliest Christmas sweater I've ever seen, and there's a lot of competition in that category (just go into any thrift or vintage store around the holidays). You can wear ugly sweaters in natural kei any time of the year though! Some of them are charming, but others are just ... odd choices. There tends to be a lot of crocheted decorations hanging off some of these sweaters.
Here is my own ugly Christmas sweater I got when I visited my folks in Illinois last year.
I call it "grandma party kei".