Peas are one crop that has huge variation. It’s hard to know if the crop will yield four tonnes per hectare or twelve. Even within small sampling plots we measured yields less than 4 t/ha and greater than 13 t/ha.
Our peas were planted into wet soil and had cold weather afterwards. Then they were savaged by pigeons. So right from the start there was variation. There were bald patches, slow germinating plants and plants with growing tips nipped out.
We put some cover cloth over plants and observed different growth. After three weeks we removed the covers and could see difference. We got a sensor that measures ground cover and compared covered and uncovered areas. There was as much as 50% difference with covered plants much bigger. We think some of the difference is pigeon related. But maybe the covers also have other effects.
We visited a number of pea crops in Central Hawke’s Bay. We saw the same variability in young crops and old. The rate of maturation is critical for vining peas as they have to peak the day (hour?) they are harvested. We’ve identified condensed flowering as a target for pea crops. We want flowering to start and stop in a short period, and pods to fill evenly to be similar maturity for harvest. In variable paddocks (uneven soils, dry areas) flowering can start and finish at different times. A long period means later pods will still be filling while the first are already getting past their prime.
We had cool conditions at the MicroFarm and think this extended the flowering period. We could see pods filling while new flowers were starting to bloom.
The variability is a problem at harvest. Setting beater speed is a difficult task when the TR range is wide; hard enough to get tougher pods open yet soft enough to save the tenderest young peas. The problem is very obvious then, but it started long ago.