Ask the gardening expert

I took a cutting from my father’s great blue Concord grape vine this fall, gave it time to root in a large pot of soil, then brought it inside. I have given it one slow-release fertilizer stick. It is growing tendrils. I will stake it, but I am afraid it will become unmanageable before many more months in the pot! When would be the best time to plant it out doors? Do you recommend any particular fertilizer at this time?

Thanks for your interesting question. Congrats on your success in growing the thing.

First, this plant won’t produce grapes this year. Grapes, like most hardy plants require a chilling period to begin the business of producing leaves, blooms and fruit. The cutting thinks it’s summer in your house, but missed its all-important winter chill.

Charles Brun, our county agent, told me grapes need at least 1,000 hours at 32 to 45 degrees in order to “break bud” — create the shoots that will bear leaves and clusters.

You have a fun project for yourself, so when the danger of hard frost is past (just to protect the many leaves you already have) plant it out and see what happens. I’m sure all the wine grape growers reading this are shuddering at my casual take, but who knows, maybe next year, you’ll see fruit.

If you take cuttings again, leave the pots outdoors for the normal cold period. However, if you’re serious about grape production, purchasing disease-free certified plants would be the way to go.

There is a lovely rose on the west side of the house we bought some years ago. The former owner remembers planting it, but not what it is. It is so fragrant, and has such nice blooms that I’d love to know what it is and how to care for it.

I’ve visited your rose, but I won’t guess at its variety — there are so many hundreds of possibilities. You describe long branches that seem to reach out, so it’s likely a climber. It also seems quite disease-free, or at least resistant.

Several mature trees 20 feet away give it protection from harsh weather, and since it’s doing well, its basic needs must be being met.

It will appreciate some basic care: In fall, cut the long branches back so the winter winds can’t whip them around, rocking the plant and loosening the soil the roots need as protection from freezing. Do any major pruning in early spring. After the branches are growing well, you might secure them horizontally to encourage blooms all along the branches instead of just at the top.

From what I’ve read I think I have a big build-up of thatch in my lawn. What is it exactly?

Is there something to spray on it to get rid of it? I would like to solve the problem in a nonchemical way, but don’t know where to begin.

The WSU site Hortsense, pep.wsu.edu/hortsense, has this to say about thatch in our area:

“Thatch is a layer of plant debris which generally accumulates at the soil surface. It consists primarily of undecomposed stem, crown, and root materials. Grass clippings contribute little to thatch formation. In healthy lawns, thatch decomposition rates balance grass growth, resulting in relatively little accumulation. However, excess fertilization, overwatering, and improper mowing will aid thatch accumulation. Also, acid soils may result in reduced thatch decomposition rates. Thatch in excess of 1/2 inch should be removed, as it can prevent water penetration. Crowns and roots can develop in the thatch rather than in the soil, making frequent watering necessary and making lawns more prone to drought injury. Certain types of grass naturally develop more thatch. Creeping bentgrasses produce large amounts of thatch, and are not recommended for home lawns.”

There are no chemical solutions recommended to control or remove thatch. Hortsense offers some management strategies:

• Deep, infrequent watering encourages deep root growth

• Mow regularly at recommended height.

• Provide adequate fertilization but no more.

• Remove thatch as necessary, preferably in early spring, using a power rake or by hand. Work in two directions (i.e. north-south, then east-west), removing 1/2 of the total desired amount in each direction.

• Reseed as needed.

• Soil aeration may be necessary to improve water penetration.

The Hortsense site has answers to most horticultural problems that arise in our Pacific Northwest.

Celeste Lindsay is a WSU-certified master gardener. Send questions to mslindsay8@gmail.com