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A field journal of theHouse&Hedgehome & garden, kept in ink
Entry 125 · vegetable

Rhubarb

Rheum rhabarbarum · Polygonaceae
full sunwater every 5 to 30 dayseasycats toxic · dogs toxic
Add to my plants
In brief
Lightfull sun
WaterEvery 5 days in the growing season, every 30 in winter
PetsCats toxic, dogs toxic

Source: ASPCA Animal Poison Control, toxic and non-toxic plants, Rhubarb entry.

Edible here means commonly eaten. Nothing on this site is medical or dietary advice.

Toxic to cats and dogs if chewed. Toxic to cats, dogs and horses. The principle is soluble calcium oxalates, causing kidney failure, tremors and drooling. The leaves are the dangerous part. Keep it where an animal that eats houseplants cannot reach it, and speak to a vet if one does. In South Africa telephone the Poison Information Helpline on 0861 555 777; in the US, the ASPCA Animal Poison Control Center on (888) 426-4435.

Rhubarb is bought as a dormant crown rather than a seed, and the crowns are sold and planted through the cold months. In the north that means roughly November to March, and they should go in soon after they arrive. In South Africa they go in during the winter, alongside the other dormant perennials and deciduous stock. Plant on ground that has had manure dug into it, with the growing buds just at the surface, and then resist for a full year. Nothing is pulled in the first season, and only lightly in the second, because the leaves are what build the crown. After that, pull rather than cut, taking no more than half the stems at once, and stop by midsummer. The leaf blades are poisonous and belong on the compost heap.

Ailments observed

Limp, drooping leavesCrown rot from a crown planted too deep or in ground that stays wet. Lift what is sound, cut away the soft tissue, and replant on a low mound so the buds sit at the surface.
Flowering at the wrong time, or boltingA flower spike thrown up by a stressed or very mature plant. Cut the spike out at the base as soon as you see it. Seeding costs the crown a whole season of stems, and a plant doing it every year wants dividing.

Filed underPlants that forgive a beginner

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