Wednesday, May 7, 2008

Seed Germination Media

This season I sold a lot of seeds to people and there seemed to be a recurring problem with germination. It took some time and ultimately some personal experience that "solved" the dilemma. It seems that because of convenience many are choosing peat pots to germinate their strawberry seeds. I too used them. I found the Ferry Morse 24 and 12 pellet "mini greenhouses" to be very convenient for varieties that I was germinating a few seeds. Many of my new varieties I only start out with 25 or less seeds.

Several customers sent emails and described their situations but it took me awhile to put it together. In most cases a few seeds germinated and then nothing happened. Looking back on this I believe that what happens is that the grower is using a cover to retain humidity. When the first few seeds germinate they take the cover off - which is also what I do. The peat pellets wick the moisture from the tray but on the surface where the seeds are sitting the peat is drying out quickly. I think the seeds may have germinated if the humidity cover had been left on. If the covers had been left on long enough for a small root system to develop the plants may have survived.

The bottom line, proceed with caution if you're using peat pellets to germinate strawberry seeds.

Another system that I tried were "Park Starts". They are styrofoam blocks with some sort of sponge type plug. By wetting the top of the plug and keeping water in the tiny shallow tray I was able to germinate seeds with this sytem. The hitch comes in transplanting. Many did not survive the transplanting process. They just withered and died. I think the cell is too small and the sponge material too dense to allow the roots to grow properly. This is speculation on my part but I saw many seedlings withering and dying. Occassionally I could revive them if they were caught in time but it took more time than it was worth.

My greatest success was with Pro-Mix BX. Unfortunately, this formulation is not and organic mix. I don't know why Premier doesn't take out the non-organic wetting agent and replace it with an organic one. As I understand it that's one issue. The other is the fertilizer charge. This is a great mix but not organic.

I am experimenting with several types of mixes. Because peat moss is not a sustainable resourse I am not including it in my trials. I am including coir and other materials that are certified organic. By the end of 2008 I should have an organic seed mix that works as well as or better than Pro-Mix BX.

BTW - I've had a little experience with ProMix Ultimate Organic and so far am not impressed. The first negative is the price. This just is not suitable for a commercial grower like me. It's cost prohibitive. I have a couple of containers of the Ultimate Organic side-by-side with ProMix BX. I think the ProMix BX is better. The plants in the BX are larger. The difference I have seen is that the BX dries out before the Ultimate Organic.

Anyone have similar or different experiences?

4 comments:

Unknown said...

"Because peat moss is not a sustainable resourse I am not including it in my trials."
Please note peat moss is sustainable. Go to this link: http://www.peatmoss.com/index.php

ascorbic said...

Any progress with this? Have any results of your trial?

Unknown said...

Peat moss takes THOUSANDS of years to grow. It isn't harvested/mined in the U.S., so it is shipped from afar. Now try and tell me that peat moss is sustainable!!!

T said...

Good info. I was curious what the best type of medium would be for strawberries. I've heard a lot of good things about pro-mix on different forums. Since I'm going to grow mine in a container, I'm trying out Gardener's Supply's organic self watering mix. If it doesn't work, I'll definitely try pro-mix.