Revision 10

What Are Gmax Crops

Gmax crops are giant mutations of regular crops in Starsand Island. When a mutation triggers, a huge version of the plant grows across the tilled soil, replacing the individual plots in the 3x3 grid. You harvest them with an Axe (not by interacting normally), and they yield the crop itself, seeds, and a Season Crop Fragment. Gmax crops are significantly more profitable than harvesting nine individual plants, making them worth targeting once your farm is set up for it.

Which Crops Can Go Gmax

Only four crops can mutate into Gmax versions, one per season. Seeds must be purchased from the Happiness Seed Shop once you reach Junior Farmer level with Graminova.

No other crops in the game can produce Gmax mutations. Flowers, trees, and standard vegetables do not have Gmax variants.

How to Trigger a Gmax Mutation

Growing a Gmax crop requires precise setup. The mutation is probability-based and is not guaranteed on every attempt.

• Step 1: Till a 3x3 grid (nine plots) of soil on your farmland using your Hoe.

• Step 2: Plant exactly 9 seeds of the same Gmax-eligible crop in the grid. Every plot must be filled.

• Step 3: Water all 9 plants daily. If using sprinklers, ensure the entire 3x3 area is covered.

• Step 4: Clear weeds promptly. Place a Rabbit Hutch nearby for automatic weed removal.

• Step 5: Apply Gmax Fertilizer III to increase the mutation chance by 15%. Applying it to the center tile of the 3x3 grid is sufficient (you do not need to fertilize all 9 plots).

• Step 6: Wait for the growing time to finish. If the mutation triggers, a giant crop appears across the entire 3x3 grid.

The crops in the 3x3 grid do not need to mature at exactly the same time for a mutation to trigger. If some plants grow slightly faster or slower due to watering or weed timing, the mutation can still occur when the final plant matures. If the mutation does not trigger, you get 9 regular crops instead. Replant and try again. Some players report needing 2 to 4 attempts before a successful mutation, though during the Intermediate Farmer certification quest, the mutation seems to trigger on the first try.

Increasing Mutation Probability

Gmax Fertilizer III

Gmax Fertilizer III is sold at the Happiness Seed Shop by Graminova once you reach Intermediate Farmer tier. It costs 320 Coins for 5 bags. The community recommends applying fertilizer to the center tile of each 3x3 grid, as one bag per grid is sufficient and the most cost-effective approach.

Gmax Fertilizer III increases mutation probability by 15%. It cannot be stacked with other fertilizer types. You must choose between Gmax Fertilizer and Ripening, Yield, or Nutrient Soil fertilizers. If your goal is a Gmax mutation, always choose Gmax Fertilizer over the growth or yield boosters.

Harvesting

The harvest prompt for a Gmax crop only appears when you stand near the top of the giant plant. Pull out your Axe and swing at it. It takes several hits to break, but you receive a generous bounty:

• Crop items: Multiple units of the base crop (significantly more than the 9 individual plants would yield)

• Seeds: Seeds for replanting

• Season Crop Fragment: One fragment per Gmax harvest (Pineapple, Watermelon, Pumpkin, or Winter Melon Fragment)

Important: When a Gmax crop grows, it destroys the tilled soil underneath. You must re-till all 9 plots before replanting.

Season Crop Fragments

Season Crop Fragments are unique items primarily obtained from Gmax crop harvests (one fragment per harvest). They can also be obtained randomly from the chef NPC as an alternative source. Each fragment type matches its crop: Pineapple Fragment, Watermelon Fragment, Pumpkin Fragment, and Winter Melon Fragment.

Each season has a themed furniture set with different piece counts:

Since you start the game in Summer, the Watermelon Fragment is the most common first target. Buy 9 Watermelon Seeds, plant them in a 3x3 grid, apply Gmax Fertilizer III to the center tile, and keep weeds clear. If you miss Summer, try Pumpkin in Autumn. Plan to grow multiple Gmax crops per season if you want to complete a full furniture set.

Profitability

Gmax crops sell for a significant premium over what 9 individual harvests of the same crop would yield. The exact value depends on the crop type and any quality modifiers, but the combination of increased crop yield plus the Season Crop Fragment makes every successful mutation more profitable than standard farming.

For maximum returns, process Gmax crop harvests into jam or pickled goods using Jam Makers and Pickling Jars, then sell via the Merchant Ship for a 200% value multiplier. A scaled-up Gmax farming operation feeding into automated processing can generate over 300,000 Coins per day.

Other Fertilizer Types

For reference, these fertilizers from the Happiness Seed Shop affect crop growth but cannot be used alongside Gmax Fertilizer on the same plot:

Everlasting Seeds and Gmax

At Senior Farmer tier, the Eternal Blessings profession skill gives you a chance to receive Everlasting Seeds when harvesting any crop. Everlasting crops do not die after harvest; they continue producing yields indefinitely. However, Everlasting Seeds and Gmax mutations are separate systems. Everlasting crops planted in a 3x3 grid can still trigger Gmax mutations, but the Gmax harvest destroys the soil and the everlasting property does not carry over to the Gmax plant itself.

Avoiding Accidental Gmax

If you want to prevent Gmax mutations (since they destroy tilled soil and replace 9 individual crops with one giant), keep your farm plots 2 tiles wide or narrower. A 3x3 block of the same crop is the minimum for a mutation, so planting in rows of 2 or using mixed crops in 3x3 grids eliminates the risk.

Known Issues

Community reports on Steam forums indicate that Gmax mutation rates may feel inconsistent. Some players report multiple successful mutations in a row, while others go 10+ attempts without success even with Gmax Fertilizer III applied. This appears to be intended randomness rather than a bug, though the base probability has not been officially disclosed.

A suggested workaround from the community: plant 3 rows of 6 crops (creating two adjacent 3x3 groups per row) and apply Gmax Fertilizer III to the center crop in each group. This lets you attempt multiple mutations per season.

Tips

• Always use Gmax Fertilizer III when attempting mutations. The 15% boost significantly reduces wasted time and seeds.

• Keep Rabbit Hutches near your Gmax plots. Weeds can break the mutation if even one plant falls behind in growth.

• Use sprinklers to cover the entire 3x3 grid. Missing a day of watering can desync plant growth and prevent mutation.

• Save Season Crop Fragments. You need one for the Intermediate Farmer quest, and extras are used in furniture crafting recipes.

• After harvesting a Gmax crop, re-till all 9 plots before replanting. The giant plant destroys the tilled soil.

• Plant multiple 3x3 grids side by side to attempt several mutations per season. More attempts means more chances.

• Process Gmax harvest yields into jam or pickled goods for maximum profit. Sell through the Merchant Ship for the 200% bonus.

• Be cautious with beehives near Gmax plots. Some players report that bee growth boosts can interfere with crop timing and seed outcomes.

• Avoid using Gathering Robots near Gmax plots. They harvest crops as they mature individually, preventing the 3x3 mutation from forming.