Pickerelweed is a plant added by Upgrade Aquatic that can be placed on dirt and clay. It comes in two variants, purple and blue, which can be crafted into purple and cyan dye respectively. It can also be boiled and subsequently consumed to restore bubbles on the player's air meter, however, it provides no saturation. Boiled Blue Pickerelweed provides 2 hunger points and 3 bubbles, whereas purple provides 3 hunger points and 2 bubbles. Its texture is animated if it is submerged in water. Pickerelweed can composted for a 30% chance to raise the level by 1 and put in a flower pot for decoration. Entities other than Pike are slowed down by pickerelweed.
Pickerelweed generates in all biomes, as long as the biome isn't icy, a desert, a beach or an ocean, but appears much more frequently in swamps, rivers and flower forests. It can additionally be found in shipwreck supply chests and can be fished up in swamps and rivers. It can only grow if it is in water, but has air above it to grow. Bonemealing a small pickerelweed will cause it to grow regardless of whether it is able to naturally, whereas bonemealing a tall one will cause it to spread.