Big Flowers are plants in Pikmin Bloom that can be found throughout the world at set landmark points. If a player is planting flowers within the Big Flower's radius, it will contribute towards blooming the Big Flower. If 300 or more flowers are planted, it will bloom and reward players who plant flowers nearby with an expedition to collect nectar from it.
If a player has not yet unlocked the ability to do expeditions, they will not get a nectar reward from a Big Flower.
A Big Flower has 4 stages:
Each time a Big Flower grows to its next stage, it will flash in light and change in appearance; the bud 2 change appears as falling petals surrounding the Big Flower rather than a change to the Big Flower itself.
When blooming a Big Flower, the types of flowers the players plant within its radius determine the type of Big Flower that will bloom. The current types are normal (tier 1), pansy (tier 2), and rose (tier 3). Tulip petals (tier unknown, only available in the Bloom Pack in the shop) are currently treated as normal petals. The flower type with a majority determines the type of Big Flower that will most likely bloom.
There is a small chance the Big Flower will bloom into the next tier flower, meaning a majority of normal flowers may produce a pansy, and a majority of pansies may produce a rose. The greater this majority, the more likely the Big Flower will bloom into the next tier flower. Roses will only produce Big Flower roses, as there is currently no higher tier.
A Big Flower's eventual bloomed color is determined by the color of the flowers that players plant within, similarly to its type, but with an additional complexity added by white. For red, blue, and yellow, the rules are simply to have the majority of their color within the Big Flower's radius to change it to their color type. For white however, it requires over 70% of the flowers to contribute towards it, but it will also count any red, blue or yellow flowers that are not the majority towards itself. For instance if there are 40 white flowers and 30 red flowers within a Big Flower, the Big Flower will say "will be a red flower" in its description because white has not reached 70%. If an additional 20 yellow and 20 blue flowers were planted within, they would contribute to white as they are less than the amount of red flowers and the Big Flower will change to "will be a ??? flower" because white + blue + yellow would then be over 70% of the contribution to the Big Flower.
If the Big Flower has a chance to bloom white, the description will say "will be a ??? flower". If it remains undetermined (continues to say ???) until it blooms, the Big Flower will bloom randomly into a white, red, yellow, or blue flower.
A player can perform strategies to increase the odds of obtaining difficult-to-get nectar from Big Flowers. They can use any 2-3 red/blue/yellow pansies combined with white petals to bloom a white pansy or a third color pansy which they may not have with the random color selection of a white flower being chosen.
A player can use unwanted petals when purposefully blooming a scarce color like blue by planting over 100 blue flowers within an empty Big Flower and then filling the rest of the amount with less than the blue in red and yellow (e.g. 110 blue, 95 red, 95 yellow). Doing this correctly will bloom a blue Big Flower, and it is easier to perform with a larger amount than 110 Blue flowers planted.
It may be possible to do this strategy using normal, pansy, and rose flower types in order to only plant 110 roses within a Big Flower in order to make it bloom as a rose.