Question
We have a house that the backyard is a very steep hill upward. We have cut down trees to allow light to the house but the vegetation went wild. We have cleared a lot and used a vegetation killer. Next year we would like to build a multi level deck into the hillside and plant a groundcover such as ivy for easy maintenance. How long until we could plant it after using the vegetation killer and what would we do until the ivy gets thick enough to choke out most of the weeds. Or is there another solution we haven't thought of.  Thanks in advance. We live in OH,

Answer
Sandy,

Different herbicides have different residue persistence.  3 weeks is usually a safe time to wait.  But again, this varies product to product.

Out here in Oregon, ivy (English ivy) is considered a noxious weed.  Once it gets established it spreads faster than you'll want to keep up with.

If it was my hillside to deal with, I'd plant a combination of  hardy shrubs (Oregon Grape, red-twig dogwood, Viburnum davidii, Rosa rugosa).  I'd plant in staggered clumps, so that there was no "straight shot" down the hill for water run-off.  These would stabilize the hillside, provide visual interest and eventually start either shading out some weeds again, or provide enough height difference that weeds wouldn't be so noticeable.

I'd also use a low maintenance grass/flower mix.  These are available at grass seed suppliers.  (for example, at   http://www.protimelawnseed.com/   look at their "environmental mixes").  They use a combination of low-growing grasses and wild flowers to provide an interesting cover that doesn't need to be mowed.

Until these get established, I'd watch what grows naturally.  I am usually pleasantly surprised by what shows up. Spot spray out only what is absolutely unacceptable (poisonous, thorny, etc).

For what it's worth,
Mark in Portland Oregon

ps.  I grew up in Elyria, Ohio