Soft Rock Phosphate

Secrets of a garlic grower

DIXON, N.M. — It was a cool morning at El Bosque Garlic Farm when we gathered for the garlic harvest a few weeks ago. Named after the Spanish word for forest, these bottomland fields nestle in a valley between the Embudo River, a rocky tributary of the Rio Grande, and the rounded sandy red foothills of the Sangre de Cristo range.

Stanley Crawford, 73, a farmer-writer who loves garlic as much as words, was loosening the fat bulbs from the soil, guiding his Kubota L2850 tractor, with its sharp horizontal discs, to cut just beneath the bulbs. It's a delicate operation, dislodging the roots without slicing through any precious bulbs of California Early, a soft-neck garlic variety that brings 75 cents a head at the Santa Fe farmer's market.

Friends and family followed behind — in a ritual that harks back thousands of years, to the Egyptians, who worshipped garlic, which is native to the Caucasus — pulling the bulbs from the warm, sandy loam and laying them in little piles facing in the same direction.

I had come here as a garlic grower, in search of secrets for a better harvest back east, having read Crawford's 1992 book, "A Garlic Testament: Seasons on a Small New Mexico Farm," as well as "Mayordomo: Chronicle of an Acequia in Northern New Mexico," an earlier work that tells the story of community water rights and Crawford's own stint as mayordomo, or ditch boss. (I had also read one of his five novels, "The Log of the S.S. The Mrs. Unguentine," which he calls "the best thing I ever wrote.")

Crawford's wife, Rose Mary, 78, bent over like a hairpin to straighten the untidy piles, calling out: "Don't muddle them. They'll get all tangled."

She met Crawford on Crete, in 1967, a few months after the military coup there.

A 34-year-old Australian, she had been a reporter for The Daily Telegraph in Sydney and a nervy publicist for the Rank Organisation, in London, where she had wined and dined celebrities like Marlon Brando and Frank Sinatra at the Savoy.

"I thought he was about 45 — he'd been smoking for years — but he was 29," she said. He had a Mercedes then, having sold the movie rights for his first novel, "Gascoyne," for $35,000 and taken off to Greece to write.

Listening to her melodious voice and looking at the lanky man in earmuffs, willing his tractor to keep a straight course down the field, I couldn't help thinking of Crawford's fictional character Unguentine and his indomitable wife, who ply the seas, warring and making love, on a barge dense with tropical trees and vegetables.

Sustainable Farming News & Biological Agriculture Information ...

Nutrition Farming® is more about insight than inputs. It is a knowledge-based approach where the aim is to reduce inputs through smarter farming and increased sustainability. This often involves synergies where certain combinations optimise outcomes and knowledge of these synergies can be the key to success with this approach. In this article I will highlight seven key combinations.

Mycorrhizal fungi and most crop plants enjoy a symbiotic relationship of tremendous benefit to both life forms. The fungi tap into the plant roots to receive a steady flow of glucose laced with nutrients that sponsor the development of a maze of hyphal filaments beneath the plant. These fine, pipe-like attachments provide the equivalent of a secondary root system that actually features up to ten times the surface area of the original roots. It would seem a no-brainer that we should nurture and protect a creature that improves root function by 1000% but that is unfortunately not the case. Arbuscular Mycorrhizal Fungi (AMF) have been decimated in our soils through a combination of acid fertilisers that sizzle these fragile filaments, salt fertilisers that dehydrate the fungi, fungicides that kill both good and bad, faulty tillage practices, and herbicides that can kill these beneficial fungi more efficiently than they kill weeds. It would also seem obvious that reintroducing these root boosters via inoculums would be a very productive strategy. This has certainly proved the case for many growers using Platform™, the new AMF inoculum from NTS. In fact, the positive feedback about this cost-effective blend has been flooding in from growers involved in both broadacre and horticulture. We have, however seen some variation in the performance of this product. There are times when colonisation is delayed and on most occasions this is related to the amount and type of phosphate applied at planting.

Maximising P Response

AMF offer a host of benefits but perhaps the best known of these relates to improved phosphate delivery. Phosphate in the soil does not remain soluble in soil solution like some minerals. Instead, it tends to stay where it is put and this immobility is further complicated by the fact that applied phosphate tends to complex with positively charged minerals (cations) like calcium and iron, forming an insoluble compound. This results in a shocking inefficiency of acid phosphate fertilisers where growers usually receive just 27% of their phosphate fertiliser investment before it becomes part of a massive, inaccessible bank of locked up P in our soils. The key to reclaiming this frozen reserve is mycorrhizal fungi, which reach out into ten times more soil volume to recover immobile phosphate while releasing acidic compounds that unlock these reserves. Inoculating with these creatures can result in greatly improved phosphate delivery to the plant with substantial reductions in the need for increasingly expensive, soluble phosphate fertilisers. However, as with all things, there are some secrets to gaining an optimal response from a mycorrhizal inoculum. The key here is to be aware of the biochemical communication between the host plant and the fungi symbiont. The plant attracts and supports this fungal partner only when it requires soluble phosphate. If you have supplied an ocean of water soluble P at the same time that you are inoculating AMF, there can be problems. The plant is aware that it is amply supplied with all of the P it needs at that time, so it shuts off the supply of food and biochemicals that are specific to AMF colonisation. Why waste your precious resources to secure a mineral you don’t need. This is the reason that we have seen a more immediate mycorrhizal response when the inoculums are introduced in conjunction with natural phosphate fertilisers like guano and soft rock phosphate. A small amount of DAP/MAP can be combined with the inoculums but it appears that it is best not to exceed 150 kg per hectare. A combination of Guano granules and DAP with a few kilos of NTS Soluble Humate Granules™ works particularly well in conjunction with AMF inoculums. The humic acid buffers the destructive heat of the acid phosphate, thereby protecting the AMF, while stabilising phosphate at the same time. This prevents phosphate from locking up with cations in the soil, effectively making it more plant available for longer.

Engineering and mining journal

Annual report

Principles of plant nutrition

Florida mineral industry, with summaries of production for 1940 and 1941

The Fertilizer Encyclopedia