Nitrogen for elderberries.

I’ve been growing elderberries for years and am comfortable with the process these days. That wasn’t always the case though. I spent quite a bit of time in the beginning looking for ways to maximize my yield. The traditional approach was to add up to one pound of high nitrogen fertilizer per tree every growing season. I’ve never used fertilizer and didn’t plan to start! The first year I added compost around the drip line for a little extra punch but felt like I was just wasting a valuable resource. The next spring I decided to try nitrogen fixing cowpeas instead. I didn’t give any thought to how it may or may not work but here’s what happens. Cowpeas are a hot weather plant so I didn’t plant them until early June. They didn’t seem to care for the shade produced by the tree and fruit thus stunting their growth. The canopy really opened up in late July when I harvested all the fruit. The peas were happy and their growth showed it! The trees make a great natural trellis and harvest has been robust the past few weeks. Once harvest is complete I’ll chop and drop the plants and seed Austrian winter peas which will grow all winter. I’ll harvest those in May and start the process over again!

Do you find the extra nitrogen makes much of a difference? Elderberries grow wild everywhere here, in very sandy, nitrogen deficient soil. They're pretty loaded every year, unless it's too hot and dry at the wrong time.

I just remembered there's a bunch growing in with black locust a few kilometres away from here. I'll have to pay more attention to those ones compared to others next year!

I’m afraid I can’t answer that. After the first year I’ve used the cowpea/winter pea setup. The only trees that don’t produce well are the ones that get around four hours of sun per day. There are wild ones here as well but they’re not very productive.

Maybe our definitions of productive are different! I'll post some pictures of our wild ones next year, if I think of it.

Just use piss, it's all natural and much better than to flush down the toilet to be wasted. Great source of potassium and phosphorus as well, you will see plants exploding in growth just after a week or two after applying a day or two's worth of urine. Works well on anything, even helps legumes to crop better in moderation despite their nitrogen fixating abilities(plus they need potassium and phosphorus regardless). If you use piss + peas or beans growing together that would be even more nitrogen for the elderberries. You can see in several studies like this one that moderate amounts of NPK fertilizer helps even peas to crop more: https://www.researchgate.net/publication/288579882_Effect_of_various_levels_of_nitrogen_fertilizer_on_the_yield_and_yield_attributes_of_pea_Pisum_sativum_L_cultivars

So both the elderberries and peas would benefit from some all-natural urine fertilizer. Good synergy overall. 👍

My elderberries keep dropping fruit before they are ripe. I wonder if the extra nitrogen would help with that?

Hey Jeff. Has this just happened one year or many? I planted mine one year then took cuttings and planted more the next. Every few years mine don’t produce at all. Many different fruit trees do this to recover after a large yield season. Since I planted mine in different years I always get a good harvest regardless.