We clipped off some grape vine from our neighbors fence & planted them where we'd like them. They're growing well, but we'd like to know what to feed them to make them healthier, etc. Do they take Miracid, a regular plant food, or what? Thanks in advance Lorraine
Lorraine--personally, we've found grapes grow well without any fertilizer. But I do hope to get over my laziness and put some composted manure around them. What I've heard from an agronomist is that in Europe the vines are often grown "lean" for best wine, that is intentionally kept underfertilized and growing on gravelly, poorish soils for best character. In California, on the other hand, they have found good results with enriching the vineyards, so the quality could improve even more. I don't think they pour on a lot of fertilizer, esp. nitrogen, however. More like a balanced feed, maybe something organic? The one thing I would consider is mycorrhiza, like the Myke product available in Canada. Apparently grape root systems are notably small and weak, because they are adapted to having these fungi partners called mycorrhize living amongst them, doing a lot of the "work" of supplying nutrients to the plant. Just a thought, otherwise like I say ours have grown great with no inputs whatever, just removed the lawn and stuck 'em in, they are getting ready to crop beautifully again this year! Glen
If these are new starts, fertilize with soluble 10-52-10 at 300 ppm (parts per million) for 2 - 4 weeks to promote root development, then switch to 20-20-20 or a slow release 14-14-14 like Osmocote or Nutricote, about a tablespoon per plant. Don't fertilize after mid July so the plant will slow down in the fall and go dormant for the winter. Ralph
Ralph and all--Ralph I understand you have quite a lot of vines, so I respect your advice. I've only got 4, and had them for a few years now. For what it's worth, I wanted to share a different perspective on fertilizing plants like grapes. My research on mycorrhizae indicates they could be quite important in the long term health and nourishment of grapes. Myco suppliers are quite unanimous in cautioning on the use of high P fertilizers...normally saying to avoid anything over 10 in the P category. The use of these soluble P fertilizers is shown to reduce or eliminate the colonization of the roots by the beneficial fungi. And it is these fungi that make most of the P available to the grape plant from ordinary soil. Otherwise, P is notoriously unavailable to plants and needs to be supplied artificially in constant small doses as it is tied up by both the mineral and humus fractions of soil. I believe that Chalker-Scott has written similar things about fertilizing roses...that P is already present in almost all soils, but needs the microbial thing happening to make it available to the plant. Adding more can reduce the microbes and produce a dependency on artificial inputs. I don't mean this in any kind of argumentative way, I really hesitated to post it because I hate seeing forums so often get into flaming discussions. I just thought it is an interesting area if people can give their (humble) input. And I do say humble coz I keep finding that the more I study plant nutrition the less I really seem to know (for sure)!!! I also realize that I am in no way commercial in my grape growing, so don't want to advise anybody whose livelihood is on the line. Just my current thoughts for what they're worth :-) Glen
One thing about learning: it helps you to realize how little you know! All my cuttings are potted with a micorrhizzae additive (Pro-Mike), and my fertilizing shedule follows that used by the propagators at the CFIA Center for Plant Health, which includes a (short and light) application of 10-52-10. I'll be investigating the interaction you mentioned. It will be interesting to find out if these two (Mike and high P) practices are at odds with each other. Thanks for the heads up. Ralph
Glen and Ralph - just a quick note of thanks - I'm enjoying this discussion, and perhaps Ralph will share the results of his experiment. Glen, don't hesitate to step in and voice a contrary thought or experience - as you can see, in this case it might prove valuable for a lot of people. As long as the discussion is about plants, whether it be learning about them or enjoying them or sharing your experiences or research, I don't think it will decay into a "flaming discussion" - and if it does, Eric and I are pretty vigilant about keeping things on track.
Re: Grape vine care : Micorrhizza vs P The dominant but by no means exclusive benefit of micorrhizzal fungi is the increased accessability of the existing soil Phosphorus to the plant. This effect peaks at 50 ppm P, and declines to the point of minimal colonization at 100 ppm P. Levels of 150 ppm P will virtually eliminate the micorrhyzae. The obvious problem with a blast of 10-52-10 is that when the P has been used up or washed out, the MF is also gone and with it much of the ability of the plant to take up P and many other nutrients. On the other hand, if you have no MF to start with (as would be the case with most potting mixes, then the 10-52-10 could fill a need for a starting plant. I guess two reasonable ideas put together do not always produce a good result! Thanks Glen. Ralph
