Planting and Fertilizing Blueberry Bushes
Someone just gave me two blueberry bushes that they ordered in late May that they failed to plant (they're been sitting in a large pot in plastic bags, with a very small amount of peat around their roots up until I got them). They do have new growth. They gave me the planting instructions, (plant each in 1.8 cubic feet of Canadian Peat Moss) that came from the grower. I contacted the grower and they said since it is so late in the season to use a water soluble fertilizer for acid loving plants every ten days through mid-August. First, I want to know if this is correct, and secondly, I'd be curious if you can recommend an organic liquid fertilizer. I would really prefer to stay away from anything that has any substance derived from an animal byproduct (ie untreated chicken litter, etc).
Being that they are going in this late, are there any other tips you could suggest for the summer and fall, or for overwintering? They are Northern Highbush varieties.
Do you know your soil pH? Blueberries prefer a pH of 5. This is the main reason why they are recommending the rhododendron mix. This late in the season I would not recommend any fertilizer. You don't want to stimulate late growth that will be killed by the first freezes in fall. The amount of peat sounds right. I would mix half and half with your soil. Most organic fertilizers are derived from manures and I do not recommend them for blueberries as they usually raise the soil pH. Most organic blueberry growers use fish emulsion sprays. I would recommend mulching the plants with 4 to 6 inches of mulch and not letting them dry out. You should prune out the older wood next spring and focus on growing new shoots and not on trying to carry a crop.