| Crop |
Plant Part to Sample |
Time of Sampling |
| Alfalfa |
Midstems for NO3-N, PO4-P, K
Leaves for SO4-S
Tops for Mo, B |
1/10 Bloom |
| Asparagus |
Fern needles 4″ tip section |
September |
| Cabbage/Lettuce |
Midrib of wrapper leaf |
Heading |
| Cantaloupe/Cucumber |
Petioles of 6th leaf/ from
growing tips 6-8 true leaves |
Early fruit set |
| Corn |
Midrib from young mature leaf
Midrib from leaf opposite ear
Leaf – young mature
Leaf opposite ear |
Before ear formation
After ear formation
Before ear formation
After ear formation |
| Cotton |
Young, mature petiole |
June thru Sept 15 |
| Onion/Garlic |
“Y” leaf from 6” plant
height to pre-harvest |
Pre-harvest |
| Sorghum/Milo |
Young mature leaf |
Pre-harvest |
| Tomato |
Full leaf of recently matured leaf (3rd – 4th leaf from growing tip) |
Anytime between 1st flower and 1st color |
| Wheat/Barley |
2” of above-ground stem |
6” tall to pre-harvest |
