The One Spring Trick That Packs Currant Bushes with Cherry-Size Berries
As fertilizer prices bite, growers are boosting yields on the cheap with compost, cover crops, and smarter soil care—proving you can harvest big without paying big.
Skip the pricey fertilizer aisle. If you want bigger, sweeter currants without a chemistry set, there is an old village trick that still slaps: feed the bushes with fish. People were doing this back in ancient times after noticing that crops near the Nile took off when they were mulched with fish scraps. Turns out, it was more than a hunch.
Why fish works so well
Fish is basically a slow-release multivitamin for plants. It brings phosphorus, potassium, calcium, manganese, iodine, and a stack of amino acids to the party.
Phosphorus fuels root growth and sets up flower buds. Calcium toughens cell walls. Iodine and manganese spark metabolic processes. Put it all together and you get currants that come off the bush bigger, juicier, and sweeter.
The catch: smell and curious pets
Yes, fish smells. And yes, neighborhood cats and dogs think you buried them a treasure. The workaround is simple: get it underground and out of reach.
For whole fish or scraps, bury them 15 to 25 cm deep around the drip line of the bush, about 30 to 40 cm out from the main stem. Backfill with soil or, even better, humus. That extra organic matter speeds up decomposition and helps keep animals from digging.
What to use and when
Right after the snow melts is prime time for currants. Small whole fish under each bush works great. Scraps are fine too: heads, tails, fins, guts. Fresh breaks down fastest, but slightly past its prime still does the job as long as it is not dangerously spoiled.
Stick to unsalted fish. Salt wipes out beneficial soil microbes. If your fish lived in brine, soak it in cold water for 12 hours first.
Prefer zero mess? Compost the fishy bits with grass clippings, sawdust, and a little soil. In 6 to 12 months you will have a phosphorus-rich compost with a tame scent profile.
Fish meal: the cleaner option
Fish meal is just ground, defatted fish waste. It barely smells and rarely attracts animals. Work it in early spring or late fall (November is perfect) at 150 to 250 g per mature currant bush, which is roughly a cup. For red currants, lean toward the high end of that range.
Make a few holes 15 to 20 cm deep around the perimeter of the canopy, tuck the meal in, cover, and water. Keep fish meal and lime separate, since lime interferes with how plants take up phosphorus.
What you can expect
Used properly, this old-school feed can move the needle. Gardeners regularly see yield bumps in the 40 to 50 percent range, and berries that size up to about one and a half times their usual.
Where it shines, and where to be careful
Currants love it, and so do fruit trees, tomatoes, and peppers. On alkaline soils, go easy. Extra phosphorus in a high-pH environment can tie up iron and zinc, leaving plants short on those essentials.
Quick plan
- Timing: after snow melt for fresh fish; early spring or November for fish meal.
- Fresh fish or scraps: bury 15 to 25 cm deep, 30 to 40 cm from the stem, around the drip line. Cover with soil or humus and water.
- Salt check: use unsalted fish only; if it was in brine, soak 12 hours in cold water.
- Fish meal: 150 to 250 g per mature bush (about 1 cup; use up to 250 g for red currant). Place in 15 to 20 cm deep holes around the canopy, cover, and water. Keep separate from lime.
- Alternative: compost fish scraps with grass, sawdust, and soil. After 6 to 12 months you get rich, low-odor fertilizer.