Fertilizing after harvest?

Cellar Rats (ITB)
1

For years I’ve heard people talk about fertilizing their vineyards after the fruit has been harvested. This is the point where vines are storing carbohydrates(fat) for the winter, which encourages healthy spring growth the following season.
My questions are, at what point is it too late to fertilize, and does it necessarily have any impact on the size and number of bunches produced the following season, or is it all about early spring growth? I’m of the understanding that bud fruitfulness is determined during the early growing season and is related more to the amount of sunlight and warmth the forming buds recieve during this period.

2

Typically we fertilize about 10 days to 2 weeks after harvest. It’s usually a low N fertilizer like a 4-18-18 @ 10 GPA. Aside from the timing of the application, the vines should still have green leaves on them so they can still “work” to store the CHO’s. This isn’t really to enhance bud fruitfulness but more to bolster the K that’s in the vine for next season (at least in our case). At bloom we are at the low end of the Potassium levels, if we didn’t fertilize after harvest of the preceding year our K’s would be very low at bloom and we’d be playing catch-up.

Craig Strehlow
Keefer Ranch Wines

3

Thanks Craig,
Welcome to the board. This was just the info I was looking for. I’m curious to hear from others with different soils. The soils in the vineyard I’m concerned abotu are 60% shale/schist and are very low in nitrogen. I wonder if adding some high grade fish emulsion(with humic acid and kelp) would be of any benefit. We get great stuff- enzymatically digested from Crescent City. Smells like fresh fish.

4

John- I use organic fish emulsion here at EMH. I apply it the evening the day of harvest (along with yucca extract as a soil penetrant, and organic humic acid). I let the irrigation run and then add the fish soup during the last 10-20% of the watering time.

5

Hey John, in addition to “fertilizer” some people spray boron post-harvest to aid in bud development…you can probably find more by googling…our local vineyard supply co recommends Solubor @ 5#/AC

this’ll get you started: http://winegrape.ag.psu.edu/docs/grapeandbarrel/GBv2no2.pdf" onclick="window.open(this.href);return false;

6

This is good stuff, [thumbs-up.gif]
Thanks Tom

7

We didn’t get any out this year, but our canopies were healthier, later, than they’ve ever been. The early rains got an incredibly thick crop of white clover covering the vineyard floor. This should produce some serious N next spring. I love cover crops that reseed themselves(especially low growing clover). We just let the last mowing go until the clover seeds out and then make our last pass, spreading and burying the seed for fall. The clover gets thicker every year and out competes most other weeds, except chickory, but that does a great job of pulling nutrients up to the surface from down deep.