How to take an accurate growing media sample

1. For the most useful results, sample media every 2–4 weeks during the crop production cycle at the same time interval after feeding or watering.
2. Collect 1.5 – 2 cups of media in a ICL-SF sample bag or in a clean plastic bag.
3. We recommend sending a composite sample. For containerized crops, gather core samples or pie-shaped wedges from the root zone from 8 or more containers. For raised or ground beds, take core samples from the root zone from 8 or more points in the area to be tested. See chart for details.
4. When testing unused media, fill pots with media, water thoroughly, then wait 1–3 days before sampling.
5. Seal the bags securely and clearly label each sample with a permanent marker. Use a unique Sample ID code for each bottle. Example: Bed #14 GER 047A, Custom Mix 40% Peat.
6. Complete the sample questionnaire using your “Sample ID code”. Retain a copy for your records.
7. Send the sample(s) and the questionnaire(s) to The ICL Specialty Fertilizers Testing Lab within 48 hours via overnight or 2–day delivery.

Fertilizer methods determine where to take growing media samples.