Has anyone ever used expired ferts?
- Thread starter MarsBarz
- Start date
Not much help on the expired part… other than to say it can easily clump up with moisture unless stored properly and it can cause rust or corrosion on other materials as it leaches chemical salts
that stuff is not necessarily organic, it starts with some organic inputs and chemical salts. Lawn & garden ferts like 10-10-10 is not really for this crop but I’m sure it’s been used. Mostly we use 2 different formulas a higher N but lower PK for veg, less N but more PK for flower, of course calcium magnesium and all the trimmings
Geoflora makes a nice organic dry mix fert, you need 2 bags, 1 for veg and 1 for flower since ratios are different. Add it to your soil mix when you make up a container, then top dress every 2 weeks and water in… we like Geoflora cuz it’s easy, works well and they are 420 site sponsor.
mostly we steer folks towards cannabis specific nutes, growing big nugs requires lots of light & nutes. There’s other stuff like MC the nute that shall not be named.. it’s good and cheap.
Whats NPK ratio of your expired fert? Got a pic or brand name?
I’m guessing you are growing in soil?
that stuff is not necessarily organic, it starts with some organic inputs and chemical salts. Lawn & garden ferts like 10-10-10 is not really for this crop but I’m sure it’s been used. Mostly we use 2 different formulas a higher N but lower PK for veg, less N but more PK for flower, of course calcium magnesium and all the trimmings
Geoflora makes a nice organic dry mix fert, you need 2 bags, 1 for veg and 1 for flower since ratios are different. Add it to your soil mix when you make up a container, then top dress every 2 weeks and water in… we like Geoflora cuz it’s easy, works well and they are 420 site sponsor.
mostly we steer folks towards cannabis specific nutes, growing big nugs requires lots of light & nutes. There’s other stuff like MC the nute that shall not be named.. it’s good and cheap.
Whats NPK ratio of your expired fert? Got a pic or brand name?
I’m guessing you are growing in soil?
- Thread starter
- #3
Yep, I'm growing in soil. The fertilizer is the PROMIX granular ferts, I have three kinds, all bought from Rona garden centre lol.
I have the nitrogen one 7-3-3, the bloom one 3-7-3, and the fruit one 4-4-8. I used them last grow, my plants seemed to grow okay. I don't really care for the last one, but the first two I plan to use and then possibly finish the grow using potassium sulphate, not sure as of yet.
I read on the internet that these ferts are okay past the expiration date so I'm not too concerned about using them past the exp. date. I just wanted to know of others experience using ferts that were expired.
Good deal, yes should be fine even past expiry.
Hopefully more will chime in later
Hopefully more will chime in later
Sueet
Well-Known Member
I can't cite specific incidences, but I've used various expired ferts numerous times. I would say in general, as long as they have been kept in reasonable storage (not wet or overly hot) they've always been fine. My houseplant food container is (sadly almost empty now) almost 30 years old, and the plants aren't complaining.
I have been using fertilizers for decades as part of my job or at home. Fertilizers do not expire. They do not suddenly disappear or turn into something else at midnight on a certain date. The dates on food or some other products are not true "expire on dates".
Dry fertilizers, including organic based ones, can last for 5 to 25 or more years as long as they are kept dry. The important word is "dry". If the bag or box has been opened up it should be closed back up properly to keep water and humid air out. Liquid fertilizers can last 10 years or longer as long as the bottle is closed up properly after use. Stored dry fertilizers should be kept cool for best shelf life. Stored liquid fertilizers should be kept cool but not allowed to freeze.
The shelf life of anything used for insect, fungus/mold or weed control will slowly become less effective even if mixed with fertilizer.
As usual there is a "however". However, if the dry or liquid fertilizer is mixed with water any unused mixture could last a day to maybe a week depending on what the concentrate was made from. Figure on mixing up only as much as will be needed that day. If more is needed in the next couple of days mix up a new batch.
I have to figure that you know what each number means and what the combination of three numbers means. Why did you choose those particular fertilizer mixes?
Why the Potassium Sulfate? I have to believe that you will be better off with the 4-4-8 fertilizer
Dry fertilizers, including organic based ones, can last for 5 to 25 or more years as long as they are kept dry. The important word is "dry". If the bag or box has been opened up it should be closed back up properly to keep water and humid air out. Liquid fertilizers can last 10 years or longer as long as the bottle is closed up properly after use. Stored dry fertilizers should be kept cool for best shelf life. Stored liquid fertilizers should be kept cool but not allowed to freeze.
The shelf life of anything used for insect, fungus/mold or weed control will slowly become less effective even if mixed with fertilizer.
As usual there is a "however". However, if the dry or liquid fertilizer is mixed with water any unused mixture could last a day to maybe a week depending on what the concentrate was made from. Figure on mixing up only as much as will be needed that day. If more is needed in the next couple of days mix up a new batch.
A couple of questions just so we are all on the same page.
I have to figure that you know what each number means and what the combination of three numbers means. Why did you choose those particular fertilizer mixes?
Why the Potassium Sulfate? I have to believe that you will be better off with the 4-4-8 fertilizer
I've used expired liquid feed with organic components with disastrous results
I use blood/fish/bone and/or Growmore granular feed in the veg garden - bought 25kg tubs years ago and they are absolutely fine
Just be sure to properly crush it up if it's clumped [or chuck the clumps in a water butt if you have one]
I use blood/fish/bone and/or Growmore granular feed in the veg garden - bought 25kg tubs years ago and they are absolutely fine
Just be sure to properly crush it up if it's clumped [or chuck the clumps in a water butt if you have one]
- Thread starter
- #8
I grabbed the 7-3-3 and the 4-4-8 from walmart to supplement the PROMIX potting soil I obtained from there as well. Promix potting soil is terrible and I'll never use it again. I didn't realize that they also sold a bloom fertilizer as well (3-7-3) else I would have grabbed that one instead of the 4-4-8. I had to go to Rona to grab the bloom one, as it wasn't sold at any of the other nearby dept stores.
From what I've read about potassium sulphate it's a power substance; buds become mighty dense after application two weeks from harvest. The NPK of that stuff is 0-0-20, therefore it's probably better to use for bud density than something with an NPK of 4-4-8
JiggiLotus
Well-Known Member
I've only had a disaster with wet nutes once. It smelled bad and the consistency was gross.. I knew better an did it anyway. Most nutes smell funky to begin with but if they're worse than they were then be cautious.
I'm a firm believer in
You feed you plant like shit, it will give you shit.
You feed you plant like shit, it will give you shit.
I recommend all three of them.
The 7-3-3 is a starter because the slightly higher Nitrogen level gives a boost to early plant growth. The plant will grow more leaves and stems. Importantly the Nitrogen is needed for chlorophyll and without enough chlorophyll the photosynthesis process slows down and the plant is weaker.
The 3-7-3 is the bloom fertilizer because of the higher Phosphorous amounts. It is the Phosphorous which promotes the growth of flowers in plants among other plant functions. For these plants the more flowers the larger and denser the flower bud.
The 4-4-8 has a higher Potassium number and fertilizers with those sorts of numbers are popular for the final stages of the plant's growth. The Potassium is needed for overall plant health. Once the plant has flowered there is just that much more plant material that has to be kept healthy so for the last several weeks the higher Potassium amounts help.
These weeks of plant age are not exact but will give an idea of how the 3 fertilizers would be used. The 7-3-3 for the first 4 weeks of plant growth. Then the 3-7-3 from the start of flowering until about 6 weeks of flower development. Then the last 2 to 4 weeks the 4-4-8 is used. New flower development has really slowed down and the Potassium kicks in to help keep the entire plant healthier which allows it to finish the flower growth.
Check every Cannabis fertilizer company to see if they have a chart or schedule for their line of fertilizers and many of them have fertilizer blends close to the ones you found. The schedule will have the gardener use the grow formula and then stop that one and start the flowering formula. Then the flowering one stops and the grower starts to use the final formula.
Or, the company has the grower follow a schedule of using some of each fertilizer blend through out the entire grow and it is the amounts that change depending on the particular week of growth that the plant is in.
For plants that will be held in a longer vegetating stage then the grower would continue the grow blend. For plants that need longer than the usual 8 weeks or so of a flowering stage then the 4-4-8 is used for the additional weeks.
I have experimented with higher Potassium amounts and it did nothing for making the buds denser. I applied high amounts of Potassium at once a week starting when the plant had been flowering for at least 4 weeks. Too much Potassium and the buds never grew large and the remaining leaves looked unhealthy.
The 0-0-20 might not be needed.
