Answer: Generally speaking you would not harvest rhubarb in the hottest part of the summer, it is normally harvested early in the season and possibly again (lightly) in the fall if it returns to active growth with the cooler weather. You can cut it off with a knife close to the base. Also remove any flower stalks as soon as they appear. This is all geared toward helping the plant stay healthy for the long term. It is a very long lived plant. I would suggest using an organic mulch year round and also top dressing with a good quality compost once or twice a year. This will help feed the soil and maintain the plant. (Cornell Cooperative Extension does not recommend additional fertilizer for this plant.) Enjoy your rhubarb!
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