Fertilizing rhodies, growing watermelon in a container
Garden writer Ciscoe Morris on when to fertilize rhododendrons, and on a variety of watermelon that can be grown in a container.
Special to The Seattle Times
The Rhododendron Species Botanical Garden Spring Plant Sale: 3-6 p.m. Friday, April 18, and 9 a.m.-3 p.m. Saturday, April 19. Weyerhaeuser Corporate Campus, West Upper Level Parking Lot, 2525 S. 336th St., Federal Way; garden admission is free with plant sale receipt (www.rhodygarden.org).
Hardy Plant Society of Washington Spring Plant Sale: 10 a.m. -2 p.m. Saturday, April 19. Center for Urban Horticulture, 3501 N.E. 41st St., Seattle (www.hardyplantsocietywa.org).
“Little Shop of Horrors”: 4:30 p.m. Saturday, April 19. The 1986 big-screen adaptation of the musical, with an introduction by Ciscoe Morris. SIFF Cinema at the Uptown, 511 Queen Anne Ave. N., Seattle; $11 (www.siff.net/cinema/big-screen-musicals/little-shop-of-horrors).
In the Garden
The verdict is out regarding whether rhododendrons need feeding on a yearly basis. Some experts swear by it while others say too much feeding can cause problems. One thing is for sure: Rhododendrons that bloom well and look healthy rarely need fertilizing.
If, on the other hand, the leaves are beginning to yellow, new leaves appear smaller than normal or your plant just isn’t blooming as well as it used to, it might benefit from a feeding. Apply an organic rhododendron food. The nutrients in organic fertilizers must be broken down by the microorganisms in the soil before they become available to the plant and therefore are incapable of burning roots.
Nutrients in synthetic fertilizers are instantly available and contain salts that can harm the shallow, airy root systems on rhododendrons, especially if they are too liberally applied. Follow the directions regarding how much to apply, and scratch the fertilizer into the soil around the drip line taking care to avoid digging into surface roots under the foliage.
Usually one feeding in early to mid-April should help green up leaves and promote healthy strong growth, but you won’t see any effect on blooming until the following spring. If you don’t notice improvement, take a branch to a Master Gardener clinic. It’s highly likely that something other than lack of nutrition is causing the problem.
Grow watermelon in a container
OK, I’m not guaranteeing it will ripen up, but thanks to a breakthrough in breeding, it may be possible to grow a watermelon in a pot on your patio. Watermelons generally take over a huge portion of the garden, and only a few varieties are capable of ripening in our area unless we get a record-breaking hot summer.
‘Sugar Pot,’ available at www.territorialseed.com, grows only to about 18 inches and is supposed to produce an 8- to 10-pound, delicious, red-fleshed watermelon that should ripen by fall if grown in a hot sunny location.
Around mid-April, begin by sowing 2 or 3 seeds indoors in a 4-inch pot filled with special seeding mix available at garden centers and nurseries. Soon after the seedlings appear, remove all but the strongest plant from the pot. Feed with half-strength soluble houseplant fertilizer and keep the starts indoors by a sunny window.
When the plants begin to become root bound in late-May or early-June, transplant each plant into a container about the size of a whiskey barrel after working about a half cup of organic tomato food into the soil. Be prepared to cover the plant with row-crop cover, especially on cold nights, until summer warmth begins in earnest.
You’ll know your watermelon is ripe and ready to harvest when the tendril near the fruit turns brown and the bottom side of the fruit turns yellow. Plan a dinner party for the end of summer. Imagine how much fun you’ll have serving your homegrown watermelon for dessert, bragging that you grew the delicious behemoth in a pot on your patio!
Ciscoe Morris: email@example.com “Gardening With Ciscoe” airs at 10 a.m. Saturdays on KING 5.
About Ciscoe Morris
Ciscoe Morris' column runs Thursdays. His show "Gardening with Ciscoe" airs at 10 a.m. on Saturdays on King 5.