Build A Ring Farm Planner logoBuild A Ring Farm Planner

Weather events

Free mutations fall from the sky. Be ready.

Weather events are the only way to roll mutations without spending cash on Sprays. Each event has a chance to fire every cycle, and once it fires every plant rolls independently for its linked mutation.

Two rolls decide everything

A mutation needs both rolls to succeed: the event has to fire, then the plant has to land it.

EffectiveRate = eventChance × chancePerRoll

P(any plant mutates) = 1 − (1 − chancePerRoll)plants

Galaxy fires on ~4% of cycles and rolls Rainbow at 1% per plant, so the effective per-plant rate is 0.04%. A full farm raises the chance that at least one plant mutates.

Every weather event

Ranked from most frequent to rarest. The rarer the event, the bigger the multiplier.

Rain

Applies wet

1.35×
Harvest multiplier

Most frequent weather event — happens roughly 40% of the time. Applies Wet (1.35x) at 8% per plant roll.

Event activation
40%
Per-plant roll
8%
Effective rate (per plant, per cycle)
3.20%

Blizzard

Applies frozen

1.75×
Harvest multiplier

Snowstorm event that applies Frozen mutation at 4% per plant.

Event activation
20%
Per-plant roll
4%
Effective rate (per plant, per cycle)
0.80%

Autumn

Applies autumn

2×
Harvest multiplier

Harvest season event that applies Autumn mutation (2x) at 3.5% per plant.

Event activation
15%
Per-plant roll
3.5%
Effective rate (per plant, per cycle)
0.53%

Black Hole

Applies void

2.25×
Harvest multiplier

Spatial anomaly that applies Void mutation at 3% per plant.

Event activation
12%
Per-plant roll
3%
Effective rate (per plant, per cycle)
0.36%

Nuclear

Applies radioactive

3×
Harvest multiplier

Triples crop value via Radioactive mutation. Time large harvests around this event.

Event activation
7%
Per-plant roll
2%
Effective rate (per plant, per cycle)
0.14%

Galaxy

Applies rainbow

5×
Harvest multiplier

Rarest standard event. Applies Rainbow (5x) at 1% per plant — the holy grail of free mutation events.

Event activation
4%
Per-plant roll
1%
Effective rate (per plant, per cycle)
0.04%

Alien Invasion

Applies alien

3.25×
Harvest multiplier

UFO scans your farm and applies the Alien mutation (3.25x) — event-only, no spray.

Event activation
2.5%
Per-plant roll
2.5%
Effective rate (per plant, per cycle)
0.06%

Trucker

Applies farm

4×
Harvest multiplier

Trucker event applies the Farm mutation (4x) — event-only, no spray.

Event activation
1.5%
Per-plant roll
1.5%
Effective rate (per plant, per cycle)
0.02%

Queen Bee

Applies honeycomb

6.5×
Harvest multiplier

Interactive special event. Collect 5 Honeycombs → 1 Honey Token. Community sources conflict on the current Honey Pot odds, including Queen Blossom at 0.1% versus 0.5%; verify the in-game table. Lasts ~5 minutes.

Event activation
0%
Per-plant roll
0.5%
Effective rate (per plant, per cycle)
0.0000%

Plant Rush

Applies

0×
Harvest multiplier

Interactive co-op event (Update 3). Defeat giant plants to earn Plant Tokens. Spend tokens at the Plant Rush shop for sprays, seeds, or Boss Boxes (Garden Golem 0.5%, Cosmic Spray 5%). Occurs ~hourly on public servers.

Event activation
0%
Per-plant roll
0%
Effective rate (per plant, per cycle)
0.0000%
Ad

What a full farm looks like

With 50 plants in the ground when the event fires. More plots means more independent rolls.

EventMultiplierChance ≥1 mutatesExpected mutated
Rain
1.35×98.5%4.00 plants
Blizzard
1.75×87.0%2.00 plants
Autumn
2×83.2%1.75 plants
Black Hole
2.25×78.2%1.50 plants
Nuclear
3×63.6%1.00 plants
Galaxy
5×39.5%0.50 plants
Alien Invasion
3.25×71.8%1.25 plants
Trucker
4×53.0%0.75 plants
Queen Bee
6.5×22.2%0.25 plants
Plant Rush
0×0.0%0.00 plants

Expected mutated = plants × per-plant roll chance. Chance ≥1 mutates = 1 − (1 − chance)^plants.

See what a mutated plant is worth

Event questions, answered with the numbers

Which weather event is the rarest in Build A Ring Farm?

Among events that roll in the weather cycle, Trucker is the rarest at 1.5% of cycles, then Alien Invasion at 2.5% and Galaxy at 4%. Rain is the most common at 40%. Queen Bee and Plant Rush show 0% activation because they are interactive events that run on their own window instead of the weather roll.

What is the strongest multiplier an event can give?

Inside the weather roll Galaxy is the top one: it applies Rainbow at 5×. Queen Bee applies Honeycomb at 6.5×, the highest event multiplier we track, but it sits outside the weather roll, so you cannot wait for it in normal play. Below Galaxy come Trucker with Farm at 4×, Alien Invasion with Alien at 3.25×, and Nuclear with Radioactive at 3×.

How likely is it that at least one plant mutates during an event?

Two rolls have to land: the event fires, then each plant rolls on its own. Multiply the two numbers for a per-plant rate — Galaxy is 4% of cycles times 1% per plant, so 0.04% per plant per cycle. The chance that at least one plant on the farm mutates is 1 minus (1 minus the per-plant chance) to the power of your plant count, which is why filling every plot beats waiting for a rarer event.

Can I buy a mutation instead of waiting for the weather?

Partly. The Gear Shop sells cash sprays for Wet at 1.35× ($10M), Frozen at 1.75× ($750M), Autumn at 2× ($1B), Void at 2.25× ($10B), Radioactive at 3× ($100B) and Rainbow at 5× ($1T). Alien at 3.25× and Farm at 4× have no shop price recorded at all, and Honeycomb at 6.5× is tied to Queen Bee — those stay event-only until a source documents otherwise.

Why are the Queen Bee numbers marked as unverified?

Because the sources contradict each other and we are not picking for you. The community wiki lists Honey Pot odds with Queen Blossom at 0.1% in one place and 0.5% in another, and nobody has re-recorded the in-game table since. Conflicted odds stay out of the calculator, and Queen Bee activation is 0 in our data because the event is not part of the weather roll.

Related guides

Events hand you the multiplier. The rest of the planner turns it into cash.

Night Market Season Pass

Pass window, free and premium rows, and exactly which cells are still unverified before you spend anything.

Fishing Frenzy

Pearl shop prices, rods, bait, event plants, the Aquarium, and Dock Otter evidence.

Queen Bee Event

Honey Pot odds, Honey Tokens, and the Transcended Queen Blossom seed.

Bees guide

Every bee and its effect, the best bees, permanent bees, and how to optimize your Hive.

Plant Rush

Boss Box drop rates, the full Plant Token shop, and the Garden Golem seed.

All mutations

Wet (1.35x) to Eclipse (12x). Trigger events, per-plant rates, and shop prices.

Profit calculator

Drop any seed into the calculator and see its real income with ring, mutation, and saw bonus layered on.

Gear shop prices

Every spray, fertilizer, and utility item with cash and Robux costs side by side.

Ring placement guide

Why Outer Ring (19x) is wasted on commons, and which seeds belong on Base, Middle, and Outer.

Seed database

Every seed, every rarity, every unit price and grow time. Sortable and filterable.

Beginner guide

Five milestones from the first lever pull to Outer Ring endgame. Follow in order.