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Core Ideas We investigated response of wheat growth to different combinations of P‐patch size and dose.Heterogeneous supply of P outperformed its homogeneous supply in terms of yield.Optimal combinations of P‐patch size and dose realized highest wheat yield. Heterogeneous supply of P generally confers a distinct advantage to crops. However, this advantage depends closely on the size of the heterogeneous patch and the dose of nutrients. This study investigated the combined effect of patch size and P dose on the growth of wheat (Triticum aestivum L.). A pot experiment was conducted with five P‐rich patches by adding one P dose (P1, 100 mg) to varying fractions of soil volume [100% (V100), 20% (V20), 10% (V10), 5% (V5), no soil (V0)], and an additional three doses of P [P2 (300 mg); P3 (500 mg); P4 (1000 mg)] were added to the first two patch sizes. A heterogeneous supply of P outperformed a homogeneous supply in terms of yield in patch sizes V0 to V20 with the same dose of P (p < 0.05). Compared with V100, however, significant less dry matter was still observed in the early stages of crop growth when P fertilizer was mixed with V0. In heterogeneous P‐supply environments, wheat yield increased markedly with patch size up to V10 and then decreased by 11% in V20 at the P1 dose (p < 0.05). Increases in P doses to P4 in V20 consistently improved wheat yield and shoot P uptake compared with V10/P1. This may be mainly attributed to improved root length and mass density inside P‐rich patches. Hence, a suitable match between P‐rich patch size and the dose of P contributes to more efficient use of P and helps to realize greater yield.

Core Ideas We assessed the movement capacity of different P.Banding P fertilizer in suboptimal placement reduced wheat yield with monocalcium phosphate.Diammonium phosphate compensated for the reduction in wheat yield due to suboptimal placement. Banding of P can increase P availability to crops. Our objective was to determine if banding two forms of P fertilizer at multiple distances from the seed can improve wheat (Triticum aestivum L.) growth and P uptake vs. broadcast P fertilizer application. Waters‐soluble and Ca2– P concentrations in soil was greater near the point of P placement when monocalcium phosphate was used compared to diammonium phosphate, while the opposite result was found when the P diffusion distance was greater than 2 cm from the P placement. Another field experiment with four application strategies (broadcasting P, banding P under the wheat row, and banding P 5 and 12 cm from the wheat row) and two P forms was conducted over 2 yr. Banding P under the wheat row increased wheat yield and P uptake regardless of the P form compared to broadcasting P. Banding 12 cm from the row resulted in a 6.0% reduction in wheat yield for monocalcium phosphate compared to broadcasting P. Banding diammonium phosphate 5 or 12 cm from the row provided yield compensations over monocalcium phosphate. Dry matter at regreening was significantly depressed for banding 5 or 12 cm from the row with monocalcium phosphate application relative to broadcasting P, while there was compensatory growth for banding 5 cm from the row after regreening. Root length proliferated with diammonium phosphate than with monocalcium phosphate regardless of band placement. Diammonium phosphate should not be placed more than 5 cm from the row to ensure maximum P uptake potential.