Blueberries: wood chips or sawdust or both?
To plant my 3 year old potted blueberry bush in the ground, my master gardener landscaper advised me to dig the hole and add two shovels full of some relatively fresh fir wood chips with compost mixed in to the clay soil. Internet research does not mention wood chips in the hole. Will fresh wood chips in the planting hole hinder root development by using up all the nitrogen in the (wood chip) decomposition process? Also which sawdust is best for mulch: fir or pine?
Marion County Oregon
I would not add wood chips to your planting hole. As you point out, the wood as it decomposes will cause a nitrogen deficiency issue for the plant. Generally it is not advised to simply amend soil in just a planting hole for any plant, but to do so on an area-wide basis if you are attempting to add organic materials to the soil. Yard debris compost is a better choice than wood chips, in any case, but even with this, one needs to monitor the plant for evidence of nitrogen deficiency. With blueberries in particular, one would also have to check soil pH to ensure that it was appropriate for the plant as well, as they prefer a soil pH of 4.5-5.5 and to get to this point often requires the addition of elemental sulfur to the soil months before planting. As for the bark mulch, either fir or pine is fine.
The OSU Publication "Growing blueberries in your home garden" can be accessed at the URL below and provides further information:
Feel free to contact me at my email directly with further questions.