This looks similar to iron chlorosis in blueberry leaves. If you have alkaline soil, and hard water(calcium carbonate), then the raspberry plant may be unable to take up iron from the soil, leading to loss of chlorophyll in the leaves. It helps to know the pH of the soil, and the pH of the water used for irrigation. If you live in an area with known hard water, you can skip the analysis, and begin watering these raspberry canes with 12 fluid ounces of 5% white vinegar per 4 gallons of tap water. Grocery stores sell 5% white vinegar, that is the standard commercial acidity used for salad dressing, or making pickles. You might see some improvement in leaf color within a week, but it will take a month or maybe 6 weeks for the leaves to look completely normal.

First, I'd check the soil to determine if it's adequately moist at the rootball.

If the soaker is the green thing in the image, it's awfully far from the as yet brand new, undeveloped root system.

The soil ph is around 5.8 last I checked (early July), The green thing in the back brings water to another zone (25ft away)where I have blueberries growing well.

I have been watering from my rain barrel when I can, ph ~4.5, we are having an unusually dry July. Avg rain fall should be about 5", to date this month we've gotten .58 of an inch.

I will hit em with some Chelated Iron tomorrow in the morning.

The soakers are under the mulch and encircle each set of brambles. The soil is well moistened at least 4-6" down around the brambles.

Any other opinions?

I am very open to trying new things, just ask my wife, I made some asparagus ice cream last night...

Wasn't my best creation to date.

We have a compost pile, and this is used on our blueberry shrubs and raspberry canes. However, when I think it might help to fertilize, I use either Miracle-Gro or Schultz's plant food. They both make an "acid loving plants" formula, and this is the one I use. Since these formulations include nitrogen, phosphorous, potassium, and other trace elements that plants need, chances are good that any nutrient deficiency in the soil will be corrected. It would be logical and straightforward to get the soil tested and then apply only what is needed to bring the nutrient profile into balance. But that would cost a lot more than the 5 dollars or so for a small package of plant food. Our raspberry bed gets cut back, and then heavily mulched with shredded tree leaves, every fall. The layer of leaves is about 8 inches thick, and it always disappears by the following fall. Most years, that is all the fertilizing that our raspberry plants receive.

As an update, the raspberry patch has really taken off in the last 2 weeks, the leaves in the pictures previously are still the same, but the rest of the canes appear more vigorous and I can see the beginnings of the flower buds ready to form on most of my canes.

I think it was a combination of the brutal heat and low precipitation we had here in NY, a application of chelated iron and a week later a 1/2 dose of fertilizer and the patch is looking great, just ordered a new jar of pectin to make Jam with them in the fall.

Congratulations! Mine did the exact same thing during the extreme heat and drought this season. About two weeks ago they took off and I have lots of berries forming. I can't wait until the plants spread and fill in there space more. We love raspberries!
Kim

Here is a link that might be useful: My Garden

It it was iron chlorosis, which it looks like, your treatment of iron chelate will not correct the yellow/white leaves, just the new growth that comes out.

If the new growth comes out green, then you might want to provide an iron treatment next year earlier in the season before the leaves start to yellow.

Beeone, yes that was my diagnosis after the fact, this morning I am going to go cut out the few affected canes, that aren't looking healthy and or don't have visible flower buds.

Thanks to all who chimed in, this is my first year actually paying attention to the garden and this site, this forum particularly has been most helpful.