Flowers failing - soil test?

[pinksand]

My parents seem to have a problem area in their foundation bed. The front of their house has a concrete path that leads from the driveway to the front steps and this path has garden space on either side of it. The area that seems to be a problem is the space between the foundation of the house and this path. It’s maybe around 8’ deep and 15’ wide… total estimate here! The back of the bed has healthy nandina and a holly bush (that I'm hoping to take out for them at some point and replace with a camellia). There’s also some variegated loriope that does fine there. I’ve included a sketch to give you a better picture of the space.



My mom has planted various annuals and perennials in the zones marked with an “X” and none have done very well. The annuals always get eaten by bunnies and deer, which are a huge problem for her garden! The deer eat all her autumn joy sedum and bee balm on the other side of the path so neither ever get a chance to bloom  Anyway, that’s a whole different problem. She has a number of bachelor buttons that did well there at one point but now they do nothing but put out a few pathetic leaves. In the past couple of years she’s tried delphinium, cone flowers, obedient plant, Japanese anemone… and probably a number of other things I'm now forgetting. The cone flowers are still there but looked pretty sad all season.

The flowers on the other side of the walkway seem to do much better. She has yarrow, silver mounds, Russian sage, mums, perennial salvia, bee balm, and coreopsis in that area among some juniper, Japanese maple, and another holly bush. The house is East facing so this bed gets morning sun and against the house where the problem area gets some shade in the afternoon as the shadow of the house grows forward. She waters both garden areas equally.

Basically, it seems as though maybe there’s something wrong with the soil. That’s pretty much the only thing I can think of at this point. To have seen the obedient plant fail here pretty much affirmed this since it has grown like mad pretty much anywhere I’ve stuck it in my own garden. Anything that has come back either doesn’t bloom or looks kind of scorched despite my mom’s watering efforts. This makes me think possible nutrient deficiency. Could it be alkaline due to all the surrounding cement? Would that cause the problem I’ve described?

I’ve often seen a soil test recommended on the forum but I'm wondering what we should specifically be looking for. Any thoughts on what may be wrong? My parents mulch this area every spring with cedar if that matters. I don't believe the soil has ever really been amended or fertilized in any way. Maybe they just need some good compost mixed in? Anyway, before my mom wastes any more money on plants next spring, I thought it might make sense to look into getting a soil test done.

Any thoughts would be appreciated!

[imafan26]

Obviously some things are growing, and you do have a variety of things growing there. I don't think it is all a soil problem but it might be that all these things have been planted a while and it is time to do some renovation. The perennials should be divided every couple of years anyway, the shrub roots may have reached out and the nutrient levels may be generally poor and filled with roots. The permanent things have to stay but taking the rest out and amending the soil with more compost and manure and fertilizing regularly might help. Selecting deer resistant plants are probably best. Make sure there are no drainage issues and the plants you chose for the location can get the sun or shade that they need. If the tree and shrub roots have invaded the area there are a couple of choices. You can choose shallow rooted plants, root prune (not recommended unless you know what you are doing not all roots can be pruned), or build berms for some of the plants so they have enough soil for their roots to grow in. This is what we did when we have to underplant the trees at the botanical garden. Some of the trees are over 75 years old and just as high. We can only plant shallow rooted, low nutrient need and shade tolerant plants beneath them. When we want to put in a bed of anything we put down about 4 inches of soil, cinder and compost and plant in that. Eventually the tree roots will invade that too but it gives the plants a better start in life at least for the first few years.

[pinksand]

Thanks for your response imafan!

My mom has trouble working in the garden these days so I've done most of the planting for her. I don't recall ever seeing any roots in the area when I've been digging but her soil isn't nearly as loose and rich as mine. My soil is dark and easy to dig into while hers is lighter with red tones and much more compact (clay?). The loriope does need dividing but other than that, none of the other plants have thrived (or survived at all in some cases) enough to actually need dividing.

I've never done a soil test before, is there anything specific I should be looking for?

[applestar]

I can't answer about soil test, but I'm trying to figure out the other issues.

Just a few feet can make a big difference in the amount of sun, especially when there is solid house shadow, so that's one thing. The shadow would lengthen and engulf the area in seasons sun angle is lower. I wouldn't expect same things to grow in X areas as where you gave marked as "garden"

The soil could be drier since "healthy" holly and nandia could be taking it all. Also, if THEY are happy, the soil in the area is probably acidic.

I'm also wondering where the down spout of the raingutter is located?

You are not going to want to change things too drastically or those nandina and holly might become less happy. Good compost always helps, though.

Have you tried lower light requirement plants like daffodils, grape hyacinths, heuchera? Wild strawberries would grow there... And maybe lowbush blueberries (great fall foliage even if it doesn't fruit as much if too much shade). Native azaleas or dwarf kalmia? ...oh but did you want annuals?

[pinksand]

I think the only reason my mom had been planting some annuals there was for longer bloom time. However, that goal hasn't been accomplished since her garden visitors devour any bud they see. Perennials would probably be preferred at this point.

It's a bit of a tricky spot since it does get some very hot sun until maybe 2pm before it gets shady. I would have thought that the obedient plant would have done okay there as well as the Japanese anemone since mine have done well in similar lighting. Coral bells are a nice idea! A dwarf Kalmia like 'Minuet' would actually look really beautiful with their house since it's white with red trim and shutters. I had kind of been thinking the soil may be alkaline since it's surrounded by cement, but the holly and nandina are super healthy so acidic soil would make sense as you said. I think some taller perennials (2-3') would be really pretty between the loriope and nandina to add some pretty blooms with the nandina as a backdrop.

Hm, maybe in the spring I'll work on digging up the holly and dig up as much soil in the "X" zones as I can without disturbing the nandina roots and add a whole bunch of compost. My mom hates the holly because it's so prickly when she has to prune it and I think a camellia would be really beautiful there in its place. It's the shadiest spot in that area so I think it would work well. Plus, if I'm already creating a mess digging up the holly that might be a good time to work on this soil situation.

The problem is I'm always making plans to work in other gardens and can't keep up with my own!

[Susan W]

This is interesting, and I am sure can be amended. There should be plenty of sun for your sunny flowers, and I am thinking too much for shady stuff.
The holly, nandina and monkey grass doing fine, but then any of those do great with whatever is thrown at them!
So, the soil. I suggest doing a deep dig and work in plenty of compost, organic matter. If there are no earthworms, it is telling, and reason to add stuff, and a few worms.
Even if the house is old, can't help but wonder if the dirt near it is in part from what was dug for foundation. It won't have the same composite as the yard further away from house.

As for bambi and bunnies, can't help much there!

[imafan26]

Camelia would be a high nutrient demand plant that is very acid loving. Remember also that some pines especially have tannins in their roots that keep other plants away. If you want to do a soil test you want to dig down about 4 inches and take a sample from the side of the hole. You don't want the top soil, you want the soil that will be in the root zone. Collect samples every 2 ft throughout the area and mix it well in a bucket. You don't want the soil too wet or too dry. Take a couple of cups of the mixed sample and send it to the lab. Usually the university extention or Master Gardeners can tell you where to send it. Fill out the form, sometimes you can download it sometimes you have to go there and pay for it before they will process it. Fill out the form and describe it as a mixed flower bed. Send a leaf sample from one of the plants that is growing there so they can test the nitrogen. The master gardeners can help you fill out the form. It takes about 6 weeks and ask for pH and basic nutrient levels and if you want organic you must specify or they will give you commercial fertilizer recommendations. In my area it costs about $25. A private soil lab will cost a lot more.