Grass and wild plants: what you can pick for a guinea pig

Why it is worth the trouble

Shop vegetables are a compromise. The natural food of a guinea pig is a meadow: grasses and herbs, dozens of species in a single day. No basket from a supermarket reproduces that mixture, and the meadow costs nothing.

When fresh grass is available it can make up most of the green ration — half and more. The rest is filled in with wild plants and garden greens.

Where you must not pick

• Along roads: that grass collects everything that leaves an exhaust pipe.
• Where dogs are walked — however clean it looks.
• On lawns in parks and by houses: they are treated against weeds.
• In fields and orchards that may have been sprayed.
• Right after rain or dew — wet grass ferments in the gut.

Grass cut with a lawnmower is not suitable at all. It is shredded, crushed, and starts to heat within half an hour — and warmed grass causes the kind of bloat that can kill a guinea pig within a day.

How to introduce it

Gradually, over about ten days. The first two days mean literally a small handful, then a little more each day. A guinea pig that spent the winter on hay and shop greens will get an upset gut from a sudden bowl of spring grass — young grass is rich in protein and poor in fibre.

About young versus mature grass: the young kind is more nourishing and suits animals that need to gain weight, while coarse mature grass settles digestion and suits the overweight. Both have their place.

What you can pick

These grow under almost every fence and suit guinea pigs without reservations.

• Dandelion — the classic guinea pig plant. High in calcium, so not dandelion alone.
• Plantain, both ribwort and greater — both safe, both good for digestion.
• Yarrow — despite the look it is not an umbellifer but a relative of the dandelion, so it is not confused with the poisonous ones.
• Nettle — only wilted or dried; fresh, it stings. Dries well for winter.
• Red clover — allowed, helpful against loose droppings. Not together with dry food.
• Knotgrass — the one that grows on trodden paths.
• Wild chicory — leaves resemble dandelion, but the bright blue flowers give it away.
• Ground elder — guinea pigs adore it, and it is rich in vitamin C.
• Chickweed — another favourite; in winter it survives under bushes.
• Dead-nettle — safe, though rarely eaten with enthusiasm.
• Shepherd’s purse — allowed, but only small amounts for pregnant animals.

What you must not pick

These grow in the same places, and they are the reason for the one rule that matters: if you do not recognise it, do not pick it.

• Cuckoo pint — highly poisonous.
• Lily of the valley — highly poisonous, leaves included.
• Autumn crocus — highly poisonous.
• Herb paris — poisonous.
• Greater celandine — do not feed, poisonous.
• Fool’s parsley — poisonous, and it resembles parsley and other umbellifers.
• Spurge — not a food plant, poisonous.
• Buttercup — mildly poisonous; guinea pigs usually avoid it themselves, but never offer it deliberately.

The real danger is not the poisonous plant itself but the resemblance. Wild garlic is confused with lily of the valley, cuckoo pint and autumn crocus — all three highly poisonous. Wild garlic gives itself away by a sharp garlic smell: rub a leaf between your fingers, and if it does not smell of garlic, drop it.

Awns — the thing nobody warns about

Awns are the sharp bristles on the seed heads of ripened grasses. They look harmless and behave like arrowheads: they catch in the coat, pierce the skin and keep travelling inside the body, never working their way back out. Ripe seed heads are best stripped off, or that grass left alone.

And one rare but real hazard: yellow oat grass. In quantity it delivers an overdose of vitamin D, which is poisoning. Simply do not build the ration on it.

Storing it

• Never keep picked grass in a bag: it heats within an hour.
• Bring home as much as will be eaten in a day.
• Spread it out thinly indoors if it is damp.
• Dry nettle, plantain and dandelion for winter; dried greens are weaker than fresh but they help in February.

In short

• If you do not recognise a plant, do not pick it.
• Never pick by roads, on lawns, or where dogs walk.
• Introduce over ten days, starting with a handful.
• Wet, warmed or mower-cut grass — no.
• Strip off ripe seed heads with awns.