Resist harvesting rhubarb too early

Q Our scraggly little rhubarb plant grew vigorously in the spring, with large stalks, which I’m told not to harvest in this, the plant’s first year in the garden. Do you agree?

A: It is commonly recommended not to harvest any stems in a plant’s first year, though you may wish to risk pulling two or three stalks from your new, yet vigorous, plant. Just water and mulch generously after.

Harvest cautiously next year, and normally the third year of the plant’s presence in the garden. A general rule is to pull no more than one-third of the stalks at a time.

Rhubarb is a spring crop, with harvesting halted in early summer. Then the plants are mulched with compost and/or composted manure and kept deeply watered over the summer to help replenish the roots.

Q My garlic planting showed signs of rust disease early this month. How can I prevent infection next year?

A: Garlic rust infections show on upper leaf surfaces as specks that turn rusty orange as spores mature. Early infections weaken the plants and reduce bulb size. Infections that show after June affect the yield minimally.

Cool, wet weather favours the disease at temperatures between 10 C and 24 C. Leaves that stay wet four hours or more are vulnerable.

Destroy infected foliage at harvest time. Do not compost it. Because the infections do not appear to spread on the bulbs, they should be fine.

Try to keep the foliage as dry as possible in the spring. If watering becomes necessary, apply the water at ground level. For the strongest, most disease-resistant plants, plant in fertile soil. Provide adequate moisture, but avoid over-watering and over-fertilizing with nitrogen. Both promote an abundance of soft growth with reduced resistance to disease.

Rust spores can over-winter on affected onion-family vegetables. Remove any infected plant material before winter. Leave as many years as possible before growing onion family plants in the same area.