What is proper way to care for rhubarb plants on the East Coast? My sister lives in Fredericksburg, VA and has not been able to keep the plant alive there. What can she do?
Rhubarb is a cool season, perennial vegetable. This means that it lives from one year to the next and produces its edible stalk during the cool weather of spring and fall. It requires temperatures of below 40 degrees F to stimulate growth and will go into dormancy when temperatures rise above 90 degrees F.
Because of this, rhubarb is best suited for Northern gardens, from Maine, south to Illinois and west to Washington state. It could be that Fredericksburg is a hair too far south to really thrive.
Rhubarb grows best in well-drained, nutrient rich, and slightly acidic soil. When preparing a rhubarb bed it is important to add plenty of well-rotted manure and compost. Because crown rot can be a problem, I suggest planting this vegetable is a raised bed to ensure proper drainage. Because rhubarb is a perennial and can produce for 6 to 8 years, select a location that is out of the way and will not be disturbed.
It is best to start rhubarb from a root rather than seed. Seedlings are slow to become established and often will not produce true. Plant the roots in early spring, about 1 month before the last frost date. Each root should have at least one prominent crown bud.
When you place the roots, keep in mind that rhubarb matures to a very large plant, some varieties reach a width of 4 -feet and a height of 3-feet. It is a good idea to space each root about 3-feet apart. Cover the crown buds with about 2-inches of soil and water in well.
The edible part of rhubarb is the stalk, not the leaves, which may be poisonous because of their high content of oxalic acid. To harvest, simply cut the stalk at ground level. To ensure healthy development, newly planted rhubarb should not be harvested for 1 year.
Once established, rhubarb should be fertilized every spring as new growth begins to emerge. Apply 1 cup of 10-10-10 fertilizer to each plant. Sprinkle it in a circle around the plant and work it into the top 2-inches of the soil.
Because rhubarb is very cold tolerant (-20 degrees F), little winter protection is needed. After the first hard freeze, collect and discard damaged stalks, and work in an appropriate amount of well-rotted manure or compost into the soil (keeping it away from the crown of the plant) and spread a 2-inches to 3-inches layer of mulch over the crowns. This is simply to prevent wind from drying out the roots.