I’m writing on the topic of Soil Testing in this blog as it’s a good time to consider doing this if you never have before, or if you haven’t done one in 4+ years. I’ll start with the ‘why’ and then walk you through the ‘how’ – as I really hope my arguments for doing this win you over!
“My soil is smart enough. My plants are all doing great.” If you can say this with full confidence, I applaud you and please don’t waste any more time reading this but hop over and check out Natalia’s amazing bird posts. If you are wondering how to get your landscape plants, (very small patch of) lawn, trees, or veggie garden to thrive then a soil test is a great place to start. And, most definitely, if you are thinking about shelling out money to buy fertilizers or compost, please consider this step first. Yes, there is a cost to having your soil analyzed but you’ll learn all you need to make sure it’s fertile and get you what you want out of your plantings – and not over-fertilize and contribute to decreasing our water quality (and simply sending your $$ into Lake Champlain).
Doing your soil testing in the fall lets you know if there are treatments that are best done now (such as incorporating lime to adjust the pH) or those you should plan on doing in the spring (like adding compost or specific fertilizers.). The test results also will tell you just how much of what’s missing needs to be added. And if you’re lucky and find out all is well with your soil, you can smile at your yard/garden all winter.
To get good results from your soil test, you need to submit a ‘good’ sample. Here is a link to the how-to sheet from the UVM Extension service:
A few things to note:
1. You don’t need a ‘soil probe’ or auger– a trowel works just fine. Just make sure to scrap off the top layer of material and dig down as described to get the soil sample. Make sure you label your bags in advance if you are submitting multiple samples!
2. For my raised beds and a field area about 30’x50’ I take about 6 samples and mix them together. The ‘zig zag pattern’ is just so you get a sample that truly represents the entire bed. The photo shows an example – probably overkill for a bed this size!
3. Mix the sample well and submit about 1 cup worth of dirt in a zip lock bag – one for each area you want results for. They cost $15/sample so think ahead about how you'll use the results.
4. You can find the form to submit with your samples here: https://www.uvm.edu/sites/default/files/Department-of-Plant-and-Soil-Science/AGTesting/Garden_hort_questionnaire.pdf
Make sure to look at the back of the form for the ‘crop codes’ – this will mean your results will come with specific information on what supplements your soil needs for the exact plants you want to grow there. One code is included in the basic test fee but if you are planting multiple veggies in a bed or aren’t sure what you will be planting you can indicate additional crops but they’ll cost you $2/each.
Now you are ready to mail in your samples. It typically takes a couple of weeks to get the test results back – faster if you opt to receive them via email. I’ll be mailing mine this week and will post the results and talk about how to interpret them when I have them in hand.
I’m curious to know if you’ve done soil testing before or plan on doing them now so I’ll try a poll:
Have you ever, or will you now, do a soil test?
0%Have done them in the past but don't need to do one now
0%I'm a believer and do them routinely!
0%You've convinced me - I'm going to give it a try!
0%Just not my thing....
Please feel free to comment and share your thoughts about soil testing - were you surprised by the results? Did it change what you grow where?
My raised beds went in at different points and probably have different soil. One bed in particular just isn't growing things. I probably should test it separately.