Overwintering potted blueberries, need some advice

I have two Dwarf Northblue plants that I purchased last spring and put in pots. I brought them indoors after about a week of cold weather. They dropped most of their leaves, and after another week or so began to rebud. Everthing seemed fine as in another week or so, they began to flower in large numbers. However, all the flowers open and then the entire flower stem dries up and falls off. I've been keeping the soil damp, but not wet, and periodically adding some Hollytone to add some acid to the soil. Is there anything I am doing wrong that's causing them not to develop fruit? Any thoughts would be welcome. Thanks.

Widget, I'm confused. It sounds like you are trying for a winter crop indoors rather than justover wintering. Mine are potted but I leave them outside with no problems. More info about what you are looking for might help.

It wasn't my intention to have a winter crop, but that would be a bonus. These are listed as zone 5 plants, and I'm in zone 4. I didn't know if they would survive outside, so I brought them in. What I'm looking for is a reason why the flowers dry up and fall off.

Widget,

I'm far from expert but I thought blueberries were more hardy than that. I'll have to do some research. As they are a temperate plant, I would expect some kind of dormancy during the winter and if you bring them indoors they may be getting some signals wrong. In my book, happy blueberries need an application of peat every year, so my first suggestion would be to test the soil. Blueberries like a fair amount of moisture, so with drier air in the winter that might also be a factor. Sorry I don't know more.

widgetdog,

Gurney's lists Dwarf Northblue as hardy Zone 3-7. So does Miller's Nursery as well. Their website says hardy to -35, developed by the University of MN. Spring Valley Nursery says hardy to -30.

I agree with krowten. I think the air may be too dry in the house, and maybe they're not getting enough moisture either. I would take them outside. Since they've been in the house all winter, you may have to do that gradually to get them hardened off.

They do need an acid-type soil, but since they are shallow-rooted plants this would only involve amending the top 6-8" if you want to set them out rather than keep them in pots. I kept mine in pots just because with my clay soil I thought it easier than trying to amend the soil. I use Hollytone for fertilizer. I added peat and perlite to regular potting soil because I could not get camellia/azalea potting mix. They need to be kept moist but not soggy, and they need really good drainage. If drainage is a problem, you can plant them in a kind of mounded-up situation for better drainage.

Good luck,

Karen

Karen,

Thanks for the support. Mine are in pots as well, b/c of the clay around here. I started out with a mix of peat in the pot, but found that the plants started to declined after a year or two. Now I put about an inch or two of peat on the top every year. Crops have steadily increased as a result and now I'm getting extra plants by digging up the root shoots that are coming on. I've been very pleased with results so far.

Widget, I do very much agree with Karen ragarding putting the plants outside, but be careful. Your climate is much more harsh than hers, and putting out an active plant from the house to freezing weather could be a big shock. I would keep them in the house at this point until your freezing weather is gone, still making sure to harden off in the spring.

I suspect you had no fruit set because you had no bees to pollinate the flowers.

Thanks for all the responses. I'll try some of the suggestions given. Maybe after setting them out this spring, they will flower again.