rhubarb

(Question)

I have 1 rhubarb plant now 5 years and a 2nd one 4yrs. Climate zone? I live in Toronto. The plants are in good nutrient soil with mostly sun and some shade. I’ve feed them both 2-3 banana peels once weekly, sometimes more often.
Why are the stalks spindly instead of thicker? I’m hoping to make rhubarb crisps but perhaps the stalks are too spindly.The plants are continuing to grow stalks(thin). Is it too late in the season to expect more growth?Any suggestions?
Thanks for your attention.

(Answer)

Thank you for contacting the Toronto Master Gardeners with your inquiry.

Rhubarb prefers to be grown in full sun, in rich lightly moist soil. Rhubarb will not thrive in a soggy location, where it will be susceptible to root rot, one of the few problems rhubarb can encounter. If your soil is heavy and doesn’t drain well. It also doesn’t do well if it has to compete with shrub or tree roots.

Spindly stalks are a sign of too little food, and often also indicate too little moisture (particularly if your rhubarb is competing with other deep-rooted plants such as a tree). Rhubarbs are heavy feeders and as a result require yearly application of compost, rotted manure, or anything high in organic matter around the crown every spring. Banana peels will take time to break down and possibly attract vermin. A spring application of compost already broken down will have a greater effect and provide a more balanced supply of nutrients.

Another possibility for spindly stalks is if the rhubarb is shaded. You mention that the site is somewhat shaded. Has the site become shaded from a nearby tree? Pruning away limbs that are shading the plant will also help.