You could hammer some woooden posts into the earth in front of the wall and string wire between them to create an inexpensive, yet large trellis. There areclimbing roses, trumpet vine, bougainnvillea, clematis or cardinal vine (if you don't have pets and children--the seeds are poisonous, same with morning glory). There is a Japanese Barberry vine, or honeysuckle. Personally, I wouldn't mix in another vine with the ivy. I think the ivy would choke it out. You could do a search on vines, so you can see photographs of various vines in bloom.

It isn't a good idea to have something climb directly up the wall because any vine which could do that without growing on a support, would have to root itself into your mortar or the wall itself, depending upon what the wall is made of. That would cause damage to the structure.

Lorna

On a solid fence I've used black plastic netting. The kind they use for deer fencing or the mesh you use to cover fruit trees. The black is invisible unless your close to the fence, and then the vine will cover it in a short time. Clematis are a lovely choice, but read up on them. There are many that need to be pruned to a few inches above the ground yearly, because they bloom on new wood, and if you don't prune them they will have bare bottoms and bloom only on the top, and this isn't a problem if this is what you want. Don't be upset with your Climbing Hydranges. They take at least 3 years to get started. After the third season it should take off. Be prepared to start to train it while the stems are flexible, because Climbing Hydranges want to sprawl on the ground.

Here is a link that might be useful: My Garden Travels

I have many of the above climbers and I love the climbing hydrangea! And you do need to help the hydrangea stay up. But I think it is worth it!I would avoid trumpet vines since they are invasive at least around here.
Happy almost spring! Sue

Vines and climbers utilize different methods to support their vertical growth. It's important to know which vines use which method to provide the correct type of support structure. Generally, these methods are broken down into 4 different catagories: winders or twiners, like wisteria or honeysuckle, where the actual growing stems wrap themselves around a support system. These need a trellis or arbor (or good strong post in the case of wisteria). Tendril vines like clematis or sweet peas have modified leaf stems that wrap around more delicate supports or even neighboring plants. These also need a trellis or arbor or some sort of netted support. Some vines attach themselves to supports by rootlets or holdfasts along the growing stems - ivy, climbing hydrangea and trumpet vines are examples of these. These are much less suited to a trellis or arbors but prefer wider, smoother surfaces like fences, walls or even tree trunks to attach themselves to. The last group are ramblers like most berries and climbing roses. These use their thorns to pull themselves up through other plants or onto the top of fences or walls and kind of anchor themselves. They generally will need help supporting themselves until they get established. They can also blow loose easily in windstorms.

Japanese barberry is not a vine but a shrub and I know of no vine called by that name. English ivy is a very aggressive evergreen vine, considered extremely invasive in some parts of the country. It will easily outcompete any other type of vine - it doesn't play well with neighbors:-)) For best success, I'd avoid mixing annual vines with perennial vines and watch out for combining vines that require different pruning methods or that have very different growth habits - one will often outgrow or smother the other.

Most perennial vines will take at least 3 years before they become well established and bloom proficiently. Climbing hydrangeas and wisteria are notorious for being slower to establish and it can take as many as 5-7 years before you see much in the way of heavy flowering. Seed grown (as opposed to grafted) wisteria may take even longer.

Thanks to all for the answers, especially for the encyclopedic one from gardengal48!