I was looking for info on trellising Triple Crown Blackberries and found tons of posts showing huge two year old plants... while my 2 yo's are no bigger than large dandylions!

I planted 6 TC's from Stark Bro's in May of 2010. 2 died that summer, 2 are literally the same size they were 2 years ago (about 6" and bushy this spring), and 2 did "ok" (or so I thought till I saw pictures of other people's). My biggest has one cane reaching about 3ft!

My question is, given that the two years they have been in the ground have been years of major drought and extreme heat, should I be concerned?

They are planted on a hillside and get morning shade, planted in fairly heavy, rocky soil I amended only a little before planting. I did irrigate through the drought summers, but they are way out on the edge of my property and would definitely look rough by the time their turn for water came 1 or 2x week.

Should I dig them up and move or just hope for a kinder summer?

This spring I've been fertilizing every 10-15 days with Stark's 22-24-12 fertilizer, hoping to actually get some growth.

I guess I am just looking for guidance, an idea of what is normal for plants surviving drought, or an admonition to just be patient!

also- I read on here and old post suggesting horse manure for Blackberries because they like the nitrogen? We have a horse- can we use manure before it's aged? and would I be correct in assuming it needs to not come in direct contact with leaves or canes?