An even bigger advantage is its easier access to lucrative mineral deposits. Uralkali's deepest mine is 450 meters (1,500 feet), while only one of Potash Corp.'s has a mining depth of 400 to 700 meters, the Saskatoon, Canada-based company's website shows. Its deepest is 1,040 meters.

BHP failed in a hostile $40 billion bid for Potash Corp. in 2010 and then proposed building the world's largest potash mine in Saskatchewan. While Melbourne-based BHP said in January that year that a final investment decision was expected in late 2011, CEO Marius Kloppers said in May he won't sign off on any major projects before the end of 2012.

Potash Corp. is expected to increase Ebitda 6.2 percent to $4.67 billion, based on 21 analyst estimates. Mosaic's Ebitda is projected to be little changed, while an 8.2 percent drop is expected for K+S Group and a 4.7 percent slump for Israel Chemicals Ltd.

Eoin Treacy's view My view – The surge in prices, from quite depressed levels, for commodities such as coffee, corn, sugar and soybeans reflects extreme weather across some of the world's most productive agricultural areas and has resulted in at least a short covering rally as speculators reverse positions. In tandem with the generally more sanguine attitude on global stock markets following last week's successful outcome to the latest Eurozone summit, this has sparked renewed interest in fertiliser shares. There has been a considerable difference between the performance of companies focusing on potash mining and those producing ammonia/nitrogen fertiliser due to the positive effects of low natural gas prices on the latter.

Among potash focused companies Potash Corp (1.23%), Uralkali, and Mosaic (0.9%) found support in the last couple weeks in the region of the lower side of their yearlong ranges. Sustained moves below their June lows would be required to question potential for some additional higher to lateral ranging. Although Yara International (2.66%) has a diversified business, its chart pattern is similar to the above companies.

K+S (3.51%), Incitec Pivot (4.04%) and Intrepid Potash have underperformed over the last year but rallied over the last couple of weeks to close their overextensions relative to the 200-day MA. They will need to sustain moves above their respective trend means to break 18-month progressions of lower rally highs and suggest a return to demand dominance beyond the short term.

Among those that have benefitted from lower natural gas prices, CVR Partners LP was spun off from CVR Energy last year and currently yields 8.54%. The share also pulled back to test the August and October lows and has bounced impressively. A sustained move below $20 would be required to question current scope for higher to lateral ranging. Terra Nitrogen LP (7.19%) accelerated higher from January to the April peak. It pulled back violently as it reverted to the mean where it has found at least near-term support. A sustained move below $180 would be required to question potential for some additional upside. Terra Nitrogen's parent, CF Industries (0.80%) has rallied back to test its peak near $200 and while it may consolidate in this area, a sustained move below $150 would be required to question medium-term upside potential.

Agrium (1.11%) is a diversified manufacturer of fertilisers and has held a progression of higher reaction lows since October. It has rallied impressively over the last five consecutive weeks and potential for a consolidation has increased. However, a sustained move below C$80 would be needed to check medium-term upside potential.