Guinea Pigs and Cut Grass in June: Post–No Mow May Precautions

As we move into June, many people are now mowing their lawns again following No Mow May. While it’s tempting to let guinea pigs enjoy the fresh greenery, it’s crucial to understand the serious risks associated with cut grass for these delicate animals.

Why Guinea Pigs Should Never Eat Cut Grass

Freshly cut grass should never be fed to guinea pigs. Once grass is cut, it begins to ferment quickly, and this fermentation process can lead to severe digestive problems, including bloat, toxin build-up, and even death in extreme cases.

Here’s why:

• Fermentation: Cut grass starts fermenting rapidly. The byproducts can disrupt a guinea pig’s sensitive gut flora and cause toxic reactions.

  
  

• Digestive Blockages: Wet or clumped grass can create compact masses in the digestive tract, potentially leading to blockages and extreme discomfort.

  
  

• Pesticide Residue: Even if you haven’t used chemicals recently, there could be lingering residues from previous treatments or contamination from nearby areas.

  
  

• Sharp Grass Blades: Very short, freshly cut grass can be abrasive and may injure a guinea pig’s mouth or digestive tract.

Can Guinea Pigs Go on the Lawn After Mowing?

Yes—but only with precautions.

You should wait at least 24–48 hours after mowing before allowing guinea pigs to access the area, giving the cut grass time to dry fully and disperse. If the weather is damp or the lawn was thickly cut, allow extra time to avoid any risk.

Safer Alternatives for Grazing

As you reintroduce mowing, here are safe ways for your guinea pigs to enjoy the outdoors:

✅ Supervised Grazing on Unmowed Areas: Let them graze in areas that haven’t just been cut. Watch them closely to ensure they only eat long, healthy grass.

✅ Indoor Housing with Unlimited Hay: Maintain a steady supply of high-quality Timothy hay, which should be the mainstay of their diet year-round.

✅ Safe, Fresh Greens: Offer a variety of guinea pig–safe vegetables like bell peppers, romaine lettuce, kale, and herbs like parsley and cilantro.

✅ Hand-Picked Grass (Carefully Selected): Pick longer, dry grass yourself from clean areas that haven’t been treated or mowed recently. Avoid wilted, damp, or clumped grass.

In June, now that mowing has resumed post–No Mow May, it’s more important than ever to avoid freshly cut grass and delay lawn access after mowing. The risks of fermentation, digestive issues, and contamination are simply too high.

Stick to hay, safe veggies, and hand-picked greens to keep your guinea pigs healthy and happy this summer.