Spraying plants with liquid seaweed extract at various intervals.

Four groups of plants are sprayed at the following intervals:

  1. No treatment
  2. Daily
  3. Every three days
  4. Weekly

The plants are sprayed from the first true leaf stage.

Alicante Seedlings W1

This is the first progress report and it will be interesting to see the results over the coming weeks.

Four weeks into the test, Rhys reports that there is no significant difference between groups – see below.

Four weeks into test
Four weeks into test

The Shirley seedlings below also show that giving seaweed extract at this stage of growth has no visible advantage.

Shirley seedlings after four weeks
Shirley seedlings after four weeks

30th March 2013 – Final Assessment

I’ve done my final measurements on the experiment and the results are fairly conclusive: NO POSITIVE EFFECT on growth of Shirleys or Alicante in the first 6 weeks after transplantation.
There may be a slight inhibition on Shirleys in terms of height.

The way I’ve done the measurements is as follows:

1. Measure height from top of soil.
2. Measure maximum ‘wingspan’ from one extremity to the other.
3. Count the number of side shoots, not including the seed leaves.

I’ve then calculated:

1. Final Height/Initial Height, averageing each figure for each treated group.
3. Final Wingspan/Initial Wingspan, averaging each figure for each treated group.

Results are as follows:


Hf/Hi: 5.1 (no treatment); 5.2 (daily treatment); 5.2 (treatment each 3 days); 5.0 (weekly).

Wf/Wi: 4.9 (none); 4.4 (daily); 4.3 (3 days); 3.9 (weekly).


Hf/Hi: 7.2 (none), 5.8 (daily), 5.7 (three days), 7.4 (weekly)

Wf/Wi: 3 (none), 5.1 (daily), 3.8 (3 days), 5.2 (weekly).

I see you reckon that the best time for seaweed is at flowering/fruiting. This seems to confirm that.

It was a good discipline to do the experiment though!