Nitrogen deficiency or something else?

Some of the leaves on my Cascade and Nugget are starting to turn this odd colour (mainly affecting Cascade). These are first year plants in 20" pots and have been doing very well up to now with bines currently over seven feet. This just started appearing over the past couple of days, mainly on the young growth near the ends of the bines and the young side shoots:

Hop Leaf Problems

I've search the forum and other sites and it sounds like a Nitrogen deficiency, but I just fertilized over the weekend with some Miracle Grow. The pots are on a drip irrigation system and I monitor the moisture level. Any other ideas or do I just need to fertilize again?

I would give it a minute. If you just fertilized then you should wait before you do it again.(could burn the plant), but it does look like you have some sort of deficiency.

If that doesn't work then try some liquid seaweed.

Over watering will cause yellowing of leaves. Are you letting the soil dry out between watering?

BTW, fertilizing a ailing plant is worse for it than leaving it alone.

"Looks" like a double header of mite damages and potassium deficiencies.

Get a cheap RapidTest pH tester from the hardware store or nursery and check that. If the pH is off then the nutrients may not be available to the plant no matter how much you give.

If your soil is constantly moist, this could be sign of Oxygen Stress to the root system. Which also mimics nutrient deficiencies as the roots shutdown and begin to rot, thus, the plant is inable to pull anything out of the soil.

Finally, check the undersides of the leaves for tiny specks and websign. If you see a blotch of black, green, or yellowish specks rub your finger over them. If they move, it's likely mites.

If you've recently fertilized and watered. Put that crap away! Nutrient deficient plants can show sign of rapid improvement when they get what they need. If the application doesn't change the appearance of the plant, then that isn't the problem.

You could, however, try a light spritzing of the fertilizer solution onto a leaf or two. If they improve, then there is a good chance theres something amiss in the soil or root system.

Thanks for the suggestions.

I'll check for mites and other pests. I did have a caterpillar munching on the leaves but I finally found and disposed of it. While trying to get rid of the caterpillar, I sprayed the plants with some Spectrum Garden Safe Fruit & Vegetable Insect Spray (which didn't seem to do anything to the caterpillar).

I use a Rapitest Soil Moisture Meter to check the moisture of the soil and it does dry out, but maybe I'll drill some more holes in the bottom of the pots to make sure it really is draining well. I'll also pick up a pH meter and test that.

I'll wait a few more days before making any adjustments. It hasn't seemed to slow the growth of the main bines though, they've both grown over a foot since the weekend.

GilaMinumBeer said:

Get a cheap RapidTest pH tester from the hardware store or nursery and check that.

If your soil is constantly moist, this could be sign of Oxygen Stress to the root system.

Click to expand...

I picked up a RapidTest pH tester and the soil in both pots is at about 6.0. I know that's at the low end of what hops prefer. I drilled a few more holes in the bottom of the pots and tested the moister levels and the soil is still very moist in the lower half of both. I've left the irrigation system off since the weekend and there's no rain on the forecast, so I'll just continue to let the soil dry out for a few more days and see how the plants respond.