I agree that Promix is a mixed bag. I've had some that truly reeked when I opened it (someone mentioned 'smells good' for the product they like) and for my seed starting environment (unheated room, 60-64F) it is way too peaty to use on its own, it is either too dry or stinkin wet that stays wet for too long in the cold. Experimenting this year just mixing the version of promix I happened to buy with the compost, and I have to say that a little goes a long way but the claims on the bag "feeds three months" is ludicrous. Just diluting the good compost with it, the greens I started recently and potting up now, a lot of yellow cotyledons telling me they want fert after two weeks, some cells the peat made a top layer absorbing the water and hardening on the surface, after couple of weeks green with algae, basically all signs of an acidified and nutrient short situation..
I use granular ferts for my seedlings as soon as I pot them up. Bone meal for tomatoes and peppers. Bone and blood meal works best for winter greens. Liquid fert I only use later to supplement feeding to mature plants that have used up their planting time quota. Because my seed starting area is cold, overwatering can be an issue especially for tomatoes. So I don't want to unevenly fertilize but I do custom water them according to needs.

This is page 4 of comments on "what to start seeds in?"

I didn't think that anyone on these 4 pages uses the same starting mix or technique. Since we are all mostly successful, I think that this shows that starting seeds is not all that complicated and there is no one magic method. Lots of methods and lots of different seed mixes or potting soils seems to work. This is good news. I guess that seeds and baby plants are not as delicate as some think.

brownrexx wrote: ↑Sun Feb 06, 2022 7:56 am This is page 4 of comments on "what to start seeds in?"

I didn't think that anyone on these 4 pages uses the same starting mix or technique. Since we are all mostly successful, I think that this shows that starting seeds is not all that complicated and there is no one magic method. Lots of methods and lots of different seed mixes or potting soils seems to work. This is good news. I guess that seeds and baby plants are not as delicate as some think.

I was getting ready to comment and count up how many different mixes were suggested, and how a newb reading this thread might be more confused after reading it than before. Even as a semi-newb myself, this thread has given me a lot to think about. And it shouldn't be that much of a surprise to me, I'm a member of some other hobby-specific forums where the same thing happens, someone asks "what's the best..." and they get 10 different answers.

@Setec Astronomy I think that the true answer for what is best would be what works for your particular budget, location, equipment and temperature. So many different methods seem to work just fine. I really don't think that it's as delicate of a process as some seem to think and for the most part, it doesn't require specialized or expensive materials.

Last year I put some potting soil into a small pot outdoors and planted a few tomato seeds so that I could get a late season young plant. With no special care, watering or fertilizer all of the seeds germinated just fine. I also get lots of volunteers growing in my compost pile and these seeds have been subjected to all kinds of stress, freezing and uneven watering.

You're surely right, as anybody who has grown ground cherries can attest to...I've had them growing out of cracks in my driveway.

I start all of my seeds in a mixture of home made compost, worm castings, bagged peat free compost and perlite. Can't recall the last time I had damping off of anything, definitely never in tomatoes. The peat free compost is usually a mixture of coir/wood fibre/composted bark/green waste compost. I used to use coir instead of the peat free, but it's become so much more expensive over the last few years and the quality of peat free composts has really improved. If I had a good source of leaf mould I would use that instead.

I have decided to sterilize in a crock pot at 180+ degrees F because it is so easy. I have ordered Espoma Bio-Tone starter fertilizer (Amazon) to add to the mix after sterilization. It has mycorrhizae fungi so it should replace some of the beneficials lost in the sterilization process.

How does mycorrhizae fungus replicate? Does it need roots or will it replicate in the mix prior to using it in a seed starter mix? If it replicates in the mix I should be able to use less.

zeuspaul wrote: ↑Tue Feb 01, 2022 8:09 pm I use recycled potting mix that I blended myself years ago. It was originally based on 511. It started as bark, peat and perlite. Now I add granular DE instead of perlite because it holds more water. I add crushed egg shells and spent tea leaves from several different teas. Also a sprinkle of blood and bone if I have it available. Also a sprinkle of Epsom salt and maybe a little fertilizer and a little potash. I sift it to remove the bigger stuff. Also add a little more peat.

I strive for a well draining mix. This year I am adding a little lime because the bark and peat may be too acidic. I vacillate between sterilizing and not. 130 degrees F saves some microbes. 180 degrees kills a lot. But no sterilization also works. IMO damping off is best prevented with growing conditions, moisture, light and temperature.

I pre germinate the seeds before planting in a rose pot.

Setec Astronomy wrote: ↑Sun Feb 06, 2022 10:13 am

brownrexx wrote: ↑Sun Feb 06, 2022 7:56 am This is page 4 of comments on "what to start seeds in?"

I didn't think that anyone on these 4 pages uses the same starting mix or technique. Since we are all mostly successful, I think that this shows that starting seeds is not all that complicated and there is no one magic method. Lots of methods and lots of different seed mixes or potting soils seems to work. This is good news. I guess that seeds and baby plants are not as delicate as some think.

I was getting ready to comment and count up how many different mixes were suggested, and how a newb reading this thread might be more confused after reading it than before. Even as a semi-newb myself, this thread has given me a lot to think about. And it shouldn't be that much of a surprise to me, I'm a member of some other hobby-specific forums where the same thing happens, someone asks "what's the best..." and they get 10 different answers.

Not to mention the boatloads of anecdotal information and marketing hype that is often not backed up by any actual scientific evidence. Gardening companies are absolutely terrible with their misleading marketing.

Probably best to lay out some basic principles to follow instead.

I am curious, why peat free? I keep peat high on my list because I trust it to be free of herbicides. Bark is also high on my list.
Composted steer manure and hay are suspect. I also don't trust green waste if it comes from the general public.

rossomendblot wrote: ↑Sun Feb 06, 2022 12:49 pm I start all of my seeds in a mixture of home made compost, worm castings, bagged peat free compost and perlite. Can't recall the last time I had damping off of anything, definitely never in tomatoes. The peat free compost is usually a mixture of coir/wood fibre/composted bark/green waste compost. I used to use coir instead of the peat free, but it's become so much more expensive over the last few years and the quality of peat free composts has really improved. If I had a good source of leaf mould I would use that instead.

zeuspaul wrote: ↑Tue Feb 08, 2022 11:58 am I am curious, why peat free? I keep peat high on my list because I trust it to be free of herbicides. Bark is also high on my list.
Composted steer manure and hay are suspect. I also don't trust green waste if it comes from the general public.

Mostly because peatlands are a massive carbon sink and it's effectively non-renewable due to the rate at which we extract it. The UK government is supposed to be banning the sale of peat to amateur gardeners by 2024, though they've said that a few times in the past already and it's never happened. I agree peat is very useful for gardeners but I just don't want to use it when there are more environmentally sound alternatives.

It's really unfortunate that green waste can't be trusted. It's mindboggling seeing some of the stuff that gets thrown in the green recycling bins.

This time every year I buy a 3.7cf bale of Promix BX and a bag of Fox Farm Happy Frog. I use the BX to start my seedlings and when ready to grow on I mix leftover BX with the Happy Frog and pot up with that mix. It has worked well for me for years. Just make sure to "wet" the BX before using.

Labradors wrote: ↑Tue Feb 01, 2022 3:37 pm Promix HP. It's very dry and prevents any damping off.

Linda

Me too!

I can no longer find Promix HP here, so I went back to using Ultrasorb, that stuff you throw on the driveway for oil spills. I learned it first at the other tomato forum we immigrated from . It works really well, easy to separate the seedlings and 0% damping off. I experienced damping off one year that's why I decided to try it. The granules are small & very dry so I line the bottom of small pots with paper towels or coffee filters I cut to size. I do the mass seeding method so I only need 1 pot per variety, 10 or more seeds to a pot.

Humic acid to aid germination.

The treatment of the seeds with diluted humate solution stimulates the cell membranes as well as the metabolic activities and thereby increases the germ rate. In this early and important phase of the plant growth humic acids promote root development, support enhanced nutrition uptake and healthy plant development.
https://www.humintech.com/agriculture/a ... -treatment


I ordered some Down to Earth Humic acid to give it a try.

The thing with potting mixes, is that they quality seems to vary too much even from batch to batch. When I get a bag that was great for my seedlings, I go immediately buy some more of the same if it's still there, for next years. As long as it's predominantly white peat based though, it will do well. White peat is quite sterile due to its acidic nature when it was harvested, also has a high aeration, which is important at stages when the plant barely absorbs any water.

A good example of inconsistent quality is this thread at TV.
http://www.tomatoville.com/showthread.php?t=48886

@ContainerTed of Muddy Bucket Farms had been using MG with success until a complete failure. I don't know what he is using now but I doubt it is MG starting mix.

A number of years ago I read a long article about recycling of food waste. It was kind of along the lines of the recent "expose's" how recycling doesn't really work, as there is too much contamination and most of what we think is getting recycled is actually going in a landfill, etc., except this was the opposite, about the industry that takes the organic waste, but has to separate out the contamination of plastic forks, etc.

Anyway, they were talking about huge digesters as an alternate to what they do now, which is basically to compost it...and sell it to...potting soil companies. Which explains why once in a while I find a piece of plastic in a bag of dirt. If you think about, there's no way you can have consistency in a product like potting soil, on the scale it needs to be produced at and where it comes from (food waste compost or not). At least that's the way it seems to me.

Potting soil isn't even soil.
I once put some in a coffee can inside a woodstove to try to kill undesirables and it fell over and all burned up.

I tried the Mosser Lee No Damp Off and found it a little strange. I used my smallest pot, about an inch square. The sphagnum moss has more/different texture than sphagnum peat moss. I planted 6 seeds in 3 different size pots and different mixtures. The small pots with the sphagnum moss hold a lot of water. What looks like a green moss grew on top. I felt like I was planting in peat moss.

After about a month the two plants in the small pots with the sphagnum moss look the best, however not by a lot. I just potted them up and they had a very well established root structure. I am guessing the *purity* of just the *clean* medium and the fertilizer made for better growth.

zeuspaul wrote: ↑Thu Feb 03, 2022 7:43 pm long fibered sphagnum moss

I was perusing HD and ran across Mosser Lee seed starter. It was less than 4 bucks for 222 cubic inches (1 gallon) with free shipping so I ordered some to give it a try. It comes directly from Mosser Lee. I am sure HD gets a cut as well as the shipper. How are they making any money?
https://www.homedepot.com/p/Mosser-Lee- ... /204372507

From their website:

Why is long fibered sphagnum moss so valuable?

Mosser Lee’s Long Fibered Sphagnum Moss is the organic answer to many gardening and indoor floral projects. Because of its abilities to both absorb and hold 20 times its weight in water and repel bacteria, long fibered sphagnum moss has been heralded by horticulturists as the best solution to several basic gardening uses and problems. Sphagnum moss is commonly used for the culture of orchids, used to line hanging baskets or as packing material to protect plant roots during shipping. It is routinely used by gardeners for a soil cover to retain moisture in potted plants, air-layering plant propagation, seed starting medium in the milled form, living wreaths and to hold moisture longer in gardens. Long Fibered Sphagnum Moss In its natural wetland habitat, the long fibers play a vital role in regulating ecosystems and provides an important buffer system for other plants, which live alongside and benefit from the water and nutrients that the moss collects.

Sphagnum moss is not peat moss

Long Fibered Sphagnum moss is the live part of the sphagnum moss plant, whereas sphagnum peat moss is a product formed from decomposing sphagnum moss. Sphagnum and sphagnum peat are often confused, each having similar and distinctive characteristics and advantages. Peat is the most common organic material used for the preparation of potting mix because of its homogeneous and favorable agronomic characteristics. However, the organic peat material does not possess long fibered sphagnum moss ability to hold suppress soil borne pathogens, such as damping off.
https://www.mosserlee.com/product/long- ... gnum-moss/

Reviews at Amazon are mixed. It is contaminated with other stuff. However it may be worth a try due to the anti-fungal properties. I may blend it with some granular DE.