I test mine for PH! It is right at 7. So I can work with the plants for there needs.

the suggestion of a soil test.. is to inform neophytes that a GOOD SOIL .. really doesnt 'need' all that much.. you accomplish this with your top dressing ...

and you are correct.. that if it thrives.. what more does it 'need' ...

the issue is really about peeps... who want to treat their plants as children.. feeling they 'need' to FEED their plants all the time ...

i once heard.. that pound for pound .. homeowners are the worst polluters on the face of the earth.. broadcasting all kinds of things that scott's and the nurseryman want to sell you .. to 'feed' your plants .... it just isnt USUALLY necessary ....

so we start by asking if they have had a soil test.. to encourage them to find out.. if anything is really 'needed' ... and when it all boils down .. 99.9% of the time.. NOTHING IS 'NEEDED' .... heck .. most the time the pH adjustment is not even needed .. [but for some weird east coast places where the bed rock is so out of whack it necessary ....]

so specifically as to you.. you have a good vibrant soil.. you really NEVER 'NEED" much of anything ... and most of the time.. no one else 'needs' anything.. so why waste the money.. the effort.. and the pollution .. just because you might think your plants 'need' something ...

they are not children.. they do not need to be fed.. nor clothed.. nor educated .... basically.. all they 'need' is water ...

a little of this or that.. isnt going to hurt.. BUT THEY JUST DONT 'NEED' IT ...

ken

ps: usually a quick call to the Ag or extension office.. can get you a general answer as the the soil in the county .... e.g. .. they might quickly say .. pH is out of whack and a test will tell you how to fix that ....

pps: i have actually had a test done.. and my pH is highish, though within normal ... but withing the range of my collections .. hosta and trees/conifers ... and within their acceptable range .... pH can interfere with the plants ability to 'use' the naturally occurring food in the soil ... so throwing fertilizer on a bad pH soil.. does not provide more to the plant ... and in fact can harm/burn the plant.. with no upside ...

I do not use chemicals or sprays! Knowing the PH of my soil tells me what Not to plant. I add a little Iron now and then when I see yellow leaves! As alkali tend to bind up the soil, Making it hard for the plants to get what they need from it.
All in all they do very well on there own.

I've never had one done. I look at it the same way you do - my plants grow very well so all must be fine, and the few things I've tried to grow a couple of time without success I just don't try to grow anymore (shasta daisies come immediately to mind). Occasionally some problem crops up and it's usually pretty obvious, and I handle on an as-needed basis as opposed to dousing the whole garden in something. As an example, when my rugosa roses show signs of iron deficiency, is easily handled with a shot of chelated iron to the bush(es) having the problem.

I've never tested soil because I wouldn't know what to do with the results. I'm definitely not going to spend money to change anything like that. It's much easier to use plants that are appropriate to the locale, like you said. Why fight an unnecesary battle? I think it's completely superfluous to the average gardener.

I guess it just depends on your thought process. Do you wonder what will grow well in your yard? Or do you decide "I will grow these things" and try to pander to them?

However, if I were going to spend a lot of money on a large-scale landscaping job, it would probably be a good idea. I would expect a professional I hired to include this as part of their preparation/consultation process.

How necessary a soil test may be depends a lot on your perception of the existing soil quality and fertility and what you intend to grow. If new to a location or garden, I generally suggest at least a baseline test to determine pH and average fertility. This at least will provide a starting point to determine if you need to amend the soil before planting or not.

If one is only planting ornamentals, additional testing is probably unnecessary. Routine mulching/topdressing or adding organic matter (like compost) periodically will ensure that soil fertility is maintained and any supplemental fertilization will be indicated by plant performance - if everything is growing well, carry on!

If one is growing edibles or harvestable crops as opposed to just landscape ornamentals, periodic soil testing maybe more appropriate. These crops do remove nutrients from the soil as they are harvested or removed each season and that is often not fully compensated for just by adding mulch or compost. Often supplemental fertilzation is very necessary and that can be most easily addressed by having a new soil test done every few years to determine what is lacking or deficient.

To expand on a couple of Ken's comments :-) Fertilizer manufacturers and suppliers, like Scotts or Miracle Gro, are in the business of selling their product. They would like you to believe that your garden will be a failure unless you use their product on a regular and frequent basis. This is a bunch of BS!! Too frequent or excessive fertilization is often worse than not fertilizing at all. It produces lush, rapid growth that is often weak and prone to insect and disease issues, plants are often far less drought tolerant and require more frequent watering and the excessive fertilizer chemicals leach in to groundwater and streams and contibute heavily to pollution.

And trees DO pull or remove nutrients from the soil, so new plantings close to the root zones of large established trees may need additional attention. Very often, this is most easily addressed by incorporating organic matter - like compost - into the area before planting and mulching on a regular basis thereafter.

I did a soil test several years ago in a new area where I was starting a large new garden bed. I'd been gardening for over 20 years, and had never done a soil test. I knew that the native soil was nutient-poor sand and that I would need to add organic matter for several years (as I've done with other areas), but wanted to understand more. Well... it was very interesting, and only cost about $7 at the time. Had it done through a local 'feed store' who then consulted about implications and how to address - including organic options. What I learned...
- ph was a bit high
- potassium was low
- phosphorus was high
The last two items were the most important -

1. use some Sul-Po-Mag for the potassium (it's organic). And potassium does leach so may need to add regularly for awhile (also then learned the symptoms so I can diagnose. Hopefully over time as the organic matter builds up in this area I'll be able to reduce or avoid the need.)
2. Stop adding phosphorus (it's bad for the lakes anyway!)No need for bonemeal or rock phospate, or any of that other stuff..
3. don't try to grow plants that really like acidic soil unless I want to address that (can do slowly by adding sulphur). And for heaven sake, don't add the wood ashes to the garden and make the ph even higher. (and don't follow other general platitudes like add lime for the tomatoes)

Also I learned that the calcium was high - so forget all those things about adding crushed eggshells...

All in all, I could have managed without a soil test, but will do a better job with one. And as an information junkie, found it all very interesting. Started my whole journey about learning about the Soil Food Web, compost tea, etc...

Beth Z5 Northern Michigan

I'm like the OP, if it grows, it grows, if it fails, then I don't try it again. Far too many beautiful plants out there to choose from to waste time and life on trying to grow something that just won't grow in my yard. I've never had my soil tested, nor do I ever plan to in the future. The only thing I need to know is where the low lying spots are in my yard and avoid planting anything that doesn't like to be underwater for weeks at a time in the spring.

Karen

At the very LEAST, it's important to have an accurate notion of what the pH of your soil is. It would be pretty difficult to know if you need to provide an acid fertilizer or to add lime without having that information. Some plants can be picky about the pH, and nutrient availability is very dependent upon soil pH.

I really have to comment on the comments that our woody plants never need supplemental fertilization. In the typical urban/suburban environment they may very well need to be provided some sort of fertilizer. Unless, of course, you are applying occasional top dressings of compost or other nutrient rich matter.

Our neighborhood soils are usually not native, have had the top layers removed for construction purposes, and are covered with hungry grasses. Very little of what the plants take up and remove from the soil is being replaced/recycled.

Some of us allow our nitrogen-rich grass blades return to the lawn after cutting, and mulch our fall leaves to use as top dressing. We use composted wood chips as mulch for our landscape beds, and tree lawns. All of those things, and more, help recycle existing plant nutrients...over and over again.

Not much need for fertilizers for those plants.

All good points but just wanted to add a couple final thoughts - I also dig several holes at least 6 - 12 inches down to get an idea of the soil profile. For example, how deep is the soil (the uppermost portion which contains most of the organic material) as opposed to say the subsoil which is usually a different color. Is it a prairie type soil or a woodland soil? I've even seen construction fill on top of good organic material and then the subsoil farther down. And if you are feeling rather industrious you can also fill said holes with water and wait and see how fast they drain over the next 24 hours. This all helps me determine what I am planting and if I am adding any compost for a new garden. But continued addition of compost is always good whether the existing soil is excellent or not.