Q&A: the best fertilizer for roses, controlling weeds

Originally published June 26, 2014 at 6:21 AM | Page modified June 27, 2014 at 9:53 AM

Gardening Events

Ciscoe’s Picks

Interbay P-Patch Lavender U-Pick Sale: 10 a.m.-4 p.m. July 5-6. 2451 15th Ave. W., Seattle (206-999-9677).

Yoga for Gardeners at Swansons Nursery: 11 a.m. July 6. Yoga instructor and gardener Theresa Elliott will teach some easy yoga poses and stretches that help before, during and after gardening. No experience necessary. 9701 15th Ave. N.W., Seattle; free (www.swansonsnursery.com/seminars-events).

“Gardening for Fragrance” at the Bellevue Botanical Garden: 7 p.m. July 8. Richie Steffen, curator for the Miller Botanical Garden, gives a presentation on fragrant garden plants that will thrive in Northwest gardens. 12001 Main St., Bellevue; $15, or $5 for Bellevue Botanical Garden members (www.bellevuebotanical.org).

In the Garden

Q: What is the best fertilizer for roses and how often should it be applied?

A: Roses have a hearty appetite, and if you keep them well fed, they’ll reward you with abundant blooms all summer long. Work a mix of organic rose food (follow the directions on the label regarding how much to apply) and 2 cups of alfalfa meal (available at most nurseries) into the soil around your roses when you prune them in early March, and again every 6 weeks during summer.

The rose food will contain all of the major and minor elements needed for healthy growth. Alfalfa meal isn’t high in the major nutrients, but it’s packed with micronutrients, growth regulators and amino acids that tell your rose “bloom, you fool, bloom!”

Wear a bandanna or hold your breath when you apply alfalfa meal, because you shouldn’t breathe the dust. Also store the alfalfa meal in a metal can in your garage or garden shed. I didn’t and every mouse in Western Washington spent the night feasting on alfalfa meal in my garage.

Finally, although most experts would tell you to stop fertilizing roses in mid-August to give your rose time to harden off before frost occurs, I always fertilize my roses one last time in late August. That’s because roses still put out spectacular displays in September and October.

Q: We are overwhelmed by weeds in our lawn and flower beds. Is there an effective way to limit weeds without using poison?

A: Weed growth exploded after our record wet spring followed by weeks of record warm weather. The most important thing to keep in mind is that the vast majority of weed seeds germinate only if they are hit by direct sunshine.

You’ve probably noticed that you spend much more time weeding in sunny open areas of the garden than in shady areas. Hence anything that keeps sunshine from penetrating to the soil surface will help keep weed populations down.

Where lawn weeds are concerned, raise the mower height and keep the grass thick and vigorous with adequate water and fertilizer. In sunny areas of the garden, open ground is the enemy. Plant closely and fill in open areas between plants with ground covers. Mulching can help as well.

Compost used as mulch won’t stop weeds from growing, but weeds tend to root in the compost layer making them much easier to pull. Woody mulches such as arborist’s wood chips can be effective at preventing weed growth, but they must be applied as thickly as possible.

Compost is a better choice where plants are frequently moved or replaced because wood chips can cause a nutrient deficiency when mixed into the soil. Even if you practice all of the above methods, don’t put away your knee pads. Weeds are just part of gardening, and if you don’t pull them before they go to seed, you’ll find yourself dealing with gazillions of their offspring next spring.

Ciscoe Morris: [email protected] “Gardening With Ciscoe” airs at 10 a.m. Saturdays on KING 5.