I have just raked up 2 trailer loads of pine needles and several more to go. I have put them in the orchard (various cool climate trees) as mulch so thought i should get some feedback here. my soil is neutral PH and heavey black soil. has anyone used pine needles as mulch?? Cathy
Re: pine needle This isn't a good idea I'm afraid. Though please - anyone - correct me if I'm wrong... Pine needles are quite acidic and will effect the ph of your soil. They do make good mulch if you're using them on a bed of strawberries (which like the acidity).
Re: pine needle Iin my personal opinion, I think the advantages of a thick pine mulch would outweigh any negative effects. A thick pine mulch makes a fine weed barrier, allows moisture to trickle through (it doesn't pack down much, although the needles do interlock, which helps prevent the mulch from blowing or washing away), and is highly valuable for shading the soil to help retain moisture. Yes, pine needles are acidic, but they are also coated with a kind of wax that slows down decomposition, so the acidity may not be much of a problem, as the soil may absorb the material so slowly that it can deal with it . Since you have a neutral soil, it may make it a tiny bit more acidic, but I just don't believe that a one-time use is going to make any huge difference. Many people consider 7 as neutral soil, but most plants prefer the pH to be closer to 6.5. So, even if it made the soil a bit more acidic, the benefits of no weed competition and keeping the soil from experiencing constant wet/dry stresses would probably outweigh the slight changes in pH. If you intended to lay down another several trailer loads in the same place in a year or two, you may want to send a sample of the existing orchard soil (where the first load was placed and has rotted down somewhat) and send along a soil sample that had no pine needles in the vicinity, and have them compared, to see what is happening. If a small amount of lime needed to be added to the orchard, I would think the other benefits of the pine mulch would offset the cost and application of the lime. Any mulch is better than no mulch, and a lot of cheap mulch is better than a thin layer of perfect, expensive mulch. IMO. Sue
Re: pine needle Heavy black soil suggests high organic matter or clay, both of which buffer against extremes of acidity or alkalinity. Blueberries also love pine needles. cheap pH test would answer the pH question and you'd be able to compare treatment (needle mulch areas) against control.
Re: pine needle Thanks for the input....haven't been online much recently. I'll continue with the pine needles with the 6 trees I have put in and spread out to suppress weeds surrounding them. I have a PH kit so will test in a few weeks and see if there is any change. Cheers Cathy PS Plenty of pine needles if anyone wants some...:lol:
Re: pine needle change will take more than a few weeks. I'd check same time next year (pH fluctuates over the course of the year based on temp and moisture in soil) and report back
Re: pine needle Thanks paul If the effect is that slow it shouldn't be a problem... i can adjust for PH over next winter. Cheers Cathy
Re: pine needle Hi Cathy, Why not add a little lime to one of the mulched trees. You could compare results when you do the Ph. test. I'd be interested to see the results. I'v always believed them to acidify the soil but i recently did Ph tests under pine trees (radiata pine). I found the Ph. to be about the same as the soil from the pasture 200 meters away (Ph, 5.8). At first i didn't beleive it, thinking id made a mistake or something. I did more tests which seemed to confirm it. I'm still not sure though because the soil looks, and smells acidic, and only low Ph.plants are growing on the edges (no legumes). Id use them anyway if i were you. A couple of years ago i heavily mulched my black current plants with pine needles. Black currents like a neutral Ph. The black currents are still very productive and i didn't encounter any problems. I probably did use lime too though; ig
Re: pine needle I mulch my blueberries with pine needles, they take a long time to break down or to alter the ph but they make an excellent week suppressant and the blueberries seem to like them.