I had Arapaho. While I wouldn't describe it as sour, I would say it wasn't very sweet. That's why I pulled it out. If the berries are dead ripe (completely plump with no shine) they are sweet enough to eat off the cane. If your picking them at a black glossy stage, that is too early. Still there are many thornless varieties that are much sweeter, so I would replace it. Your probably in a warm enough zone to try some of those new releases from Oregon. If that's the case, I wouldn't fool around with the Arkansas releases.

Blackberries don't need acid unless your soil is pretty alkaline. Are you thinking of blueberries?

We live near Montgomery AL (zone 8A) and grow 5 varieties of Arkansas released blackberries (Arapaho, Navaho, Apache, Ouachita and Natchez) and they are all tasty off the vine, especially Navaho, when they are ripe. However, as olpea noted, adding the acidifier may not have helped matters. For blackberries, we have found that the soil PH should be around 5.5 to 6.5 for quality growth and we water every other day from the time they start to leaf out until the end of October. We fertilize with 13-13-13 in February and then spray a fish/seaweed combination from Neptunes Harvest on the plants every two weeks until the berries start to ripen. We also give them some Potasium (0-0-60) in the fall to replenish what was taken from the soil during the growing season. Here's a link we referenced often when we first started building our U-Pick. I realize it's related to a commercial operation but there is a lot of good information in it.

Hope this helps,

Ken Barber
Barber Berry Farm

Here is a link that might be useful: Growing Blackberries in North Carolina

Thanks for the info my soil ph likes to stay above 7.o because we have alot of limestone and our water is alkaline also, I didn`t add to much sulfer just about a small hand full spread out around the plants just to drop the ph slightly. I am picking them at gloss stage so I will let them dull before I pick to see if that was the factor. Thank you Ken for your advice I will add potasium at the end of the season and follow your advice for next year. I would trade to other cultivars but dang these were good quality plants that were not cheap. Instead of fresh eatting I may just use for cooking or jams. Thanks :o)Deanna

Can someone mention a few names for the new Oregon releases?

Black Pearl, Metolious are newer varieties offered by Raintree.

Ask me in a month or so and I can tell you about many of them, I will have fruits for the first time from several of the Oregon types. Black Pearl proved to be insufficiently hardy for me.

Most of the time being picked too early is the problem anyway -- put a pack of newcomers in a blackberry patch and they will all go for those nice shiny ones and not the old dull ones.

Scott

It maybe to late this year but K-mag fertilizer make any fruit sweet just handful to each plant. Sourses will be any place that mix fertlizer in large amounts. Makes all melons sweet. I get by 5 gallon full at place that does fertilizing to pasture materal large white prills. K-mag works better than potasium 0-0-60 K-mag has magnesium that along with potasium makem sweet.

Had the same problem as Olpea, with Arapaho and Navaho. I ended up pulling them and putting in Triple Crown. They were much sweeter and did not have to be plump ripe, dull for me. The only fertilizer I used on both was 14-14-14 in the spring.

You know the advertisements are all misleading, I wanted a bush that did not have thorns and that didn`t need to much support but that was sweet to. I should have asked on this forum before I bought, next time I will ask everyone. Well if all I wanted to do was take pictures of beautiful plants I got them. lol.:o)Deanna