foliar feeding with kelp

Hi All; Recently I was told about spraying kelp on the top and bottom of leaves as an organic fertilizing method . Although sceptical, I did some online research and decided to try some. I found a wonderful company (kelp4less) with great prices and good information. After a few days, a noticeable difference in how happy the tomato plants were looking was apparent. After one week it was obvious that the foliar fed plants were doing better than the control plants that had not been sprayed with the kelp. I will be using this the rest of this growing season on all of our garden and I am already thinking about next season and how well things might do if I start foliar feeding when they are small ! Will I keep using traditional soil fertilization methods , of course but I thought I would share something that seems to work !

Hi Thomas,

you can use refractometer to measure is certain foliar feed working or not. If the Brix is raised after 2h of sunshine it is working. If it is not increased (or is lower) then don't use it.

How are the plants uptaking nutrients from foliar feeding? Or is the benefit from something else?

Joe

Joe Camarena wrote:How are the plants uptaking nutrients from foliar feeding? Or is the benefit from something else?

Joe

Here's a brief explanation. http://en.wikipedia.org/wiki/Foliar_feeding

Many nutrients are precipitated near active volcanoes. Plants that make good use of foliar feeding, should gain some advantage in those areas.

Dale, that is not what I was taught in biology. Is this a case of modern science being proven wrong, or that foliar feeding is being misunderstood on how it benefits the plants?

The stomata are part of the epidermis. Right there that contradicts the link you posted. Sorry, I do not except Wiki for scientific references. Next thing that article says is that plants have nutrient exchange through their leaves. This is also not true. Only gas exchanges are made through the leaves.

I really want to understand foliar feeding but have not found any sound scientific proof that the plant is benefitting from feeding.

Is the benefit to the plant from foliar spraying in some other action? My hypothesis is that the act of spraying the plants with nutrient rich sprays does two things. One, it cools the plant. Two, the spray drips to the soil and is absorbed through the roots.

Joe

Meh. Most of what I was taught in biology was either wrong or so much of a 'half-truth' that it was as good as wrong.

The wikki lists a few references, at least one of which still seems to link to a downloadable pdf which might or might not be worth believing. I don't think the stomata being 'part of the epidermis' really contradicts anything either, at least not the way I view the epidermis. I see the epidermis as that particular layer of cells, and the stomata as holes in that layer. It gets a bit metaphysical trying to decide if the holes are part of the layer or not, but what it's trying to say is that stuff can pass either through the holes or through the layer of cells.

"Only gas exchanges are made through the leaves" is such a sweeping statement that it scarcely meets our publication standards, especially as that is exactly what we are trying to determine here.

Gardenweb has an interesting thread on the subject here.

But if you really want to know something, the only way is to devise your own tests and try it yourself.

I mostly see foliar feeding used in greenhouse operations that use hydroponics or soil mixes that exist mainly to support the plant. They get results. Not my favorite type of agriculture but the plants are obviously absorbing nutrient.

Pitcher plants grow in marl ponds. The conditions don't allow them to take in nitrogen. In the wild, insects are trapped and nitrogen is absorbed from them. These plants can be grown in a sun room without insects if a foliar spray is employed. The substrate is not conducive to feeding them nitrogen and the plants don't naturally absorb their nitrogen from the roots. Therefore, I assume that the foliar spray is working as intended.