Rhubarb time

Horticulture Hints

We know it, most love it, and many are anxiously watching and waiting for their rhubarb to become large enough to enjoy the first harvest of the season. Although best to do so early spring – but with our crazy Iowa weather this year – it’s still not too late to give your rhubarb a dose of fertilizer.

Just a one-time application of well balanced fertilizer, such as 10-10-10, is usually all you will need to make during the growing season.

First time rhubarb grower? Plant new plants in a sunny, well-drained site, about three feet apart. Place each root so that the bud is just below the soil surface. Good drainage is essential to avoid disease that may be present in overly moist soil. During a wet year or in a poorly drained sites, root-rot fungus can attack the plant. Replant in a new location if this occurs.

Leaves of rhubarb are poisonous, but the stalk is edible. It is best to harvest rhubarb by pulling out the individual stalks, rather than cutting, which creates an open wound for pest invaders. Wait to harvest new plantings until their third year of growth, as to allow the young plants to build up energy reserves. On newer stands, it is recommended to stop harvest by mid-June, as to allow food reserves to build up for next season’s crop.

Now, who’s ready for pie?

Did you know? Older rhubarb plants produce hollow stalks that form seed heads that should be pulled out just as soon as they appear. Presence of seed heads indicate your plant needs to be divided. Plants producing small, spindly stalks also need to be divided. Divisions should be made in early spring, each root division should have a strong bud.

Horticulture Questions? Contact McCormick at yvonne@iastate.edu for information or advice.