I apply liquid fertilizer via an injector and my drip system, and occasionally with a watering can when I don't have the drip system in place yet.
Whenever I read a fertilizer bottle/package/instructions it typically says to apply once or twice a month.
Is this because plants need a jolt of fertilizer and then a "rest" period? Or is it because the writers assume people won't make the effort more than once or twice a month?
Would plants prefer a continuous stream of less-concentrated fertilizer if it were available?
BTW I'm asking mostly with regard to vegetables.
- TheWaterbug
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- rainbowgardener
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I certainly agree with Gary that you don't want too much. Some things like tomatoes and peppers are more productive when a little bit stressed for water/nutrients.
OTOH, I doubt "jolt and rest" is a natural cycle. I expect that naturally plants are continuously taking what they need from the soil. That is the point of compost and other "slow release" ways to add nutrients to the soil. If you can mimic that, your plants would probably like it.
For fruiting plants, again like the tomatoes and peppers, you want low nitrogen, not balanced, fertilizer. I don't know if you have any way with your drip system to give different mixtures to different parts of your garden.
OTOH, I doubt "jolt and rest" is a natural cycle. I expect that naturally plants are continuously taking what they need from the soil. That is the point of compost and other "slow release" ways to add nutrients to the soil. If you can mimic that, your plants would probably like it.
For fruiting plants, again like the tomatoes and peppers, you want low nitrogen, not balanced, fertilizer. I don't know if you have any way with your drip system to give different mixtures to different parts of your garden.
- TheWaterbug
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I probably should have worded the original question better. Given the recommended application rate of fertilizer, e.g. X lbs/acre/month or whatever, it is better given continuously or in a more concentrated burst?
I'm guessing the former, but I'm hoping to get some insight from folks who have been doing this far longer than I
Regarding my existing system, I have a two-zone timer and a drip system that I reconfigure throughout the season as I plant new areas. I have another two-zone timer and a single zone timer that I can put in whenever I want. I also have two 1 pint injectors, so I can put the fertilizer where I want to.
But the 1 pint injectors empty in approximately 35 gallons, and my watering schedule dumps many time that amount each week, so each fill is less than a full "dose." So I'm wondering if I should just fill it up every week.
I'm guessing the former, but I'm hoping to get some insight from folks who have been doing this far longer than I

Regarding my existing system, I have a two-zone timer and a drip system that I reconfigure throughout the season as I plant new areas. I have another two-zone timer and a single zone timer that I can put in whenever I want. I also have two 1 pint injectors, so I can put the fertilizer where I want to.
But the 1 pint injectors empty in approximately 35 gallons, and my watering schedule dumps many time that amount each week, so each fill is less than a full "dose." So I'm wondering if I should just fill it up every week.
as Joan says . . . can we talk?
excepting hydroponic systems - - - -
you put some fertilizer "down" - whether that's granular, powdered, liquid, in solution, foliar feeding, not the issue.
for "optimum" - however one can define that - plants like to eat daily. they got roots for that.
"fertilizer" does not "go down" and twenty seconds later "disappear" - there is a persistent factor which varies "wildly to the nth degree" based on chemical source, "organic source" - solid - slow release/not slow, liquid, etc.
basically by whatever 'method' you're tossing some NPK into the soil. the plants uses some, some leaches away. how fast the NPK is available / leaches depends on the NPK source. which is why the organic crowd goes with the manure bit - sits there, releases 'slowly' over weeks.
pellets of Miracle Grow 30-30-30 tossed on the surface work fast; and probably leach away in a couple days - perhaps stretched to 2 weeks - depending on how much water / irrigation / rain / slope / run-off is "involved" in your specific situation.
all of the above serves to discount the "burst then starve" theory. there's no even chem-to-the-max fertilizer I'm aware of that "disappears" in 24 hours - so if you've got plants in dirt, daily fertilizing is not indicated.
admittedly, this is a very complex question involving a lot of factors - the hydroponic crowd feeds constantly - why? because the roots are not in soil - and the nutrient mix drains away.
excepting hydroponic systems - - - -
you put some fertilizer "down" - whether that's granular, powdered, liquid, in solution, foliar feeding, not the issue.
for "optimum" - however one can define that - plants like to eat daily. they got roots for that.
"fertilizer" does not "go down" and twenty seconds later "disappear" - there is a persistent factor which varies "wildly to the nth degree" based on chemical source, "organic source" - solid - slow release/not slow, liquid, etc.
basically by whatever 'method' you're tossing some NPK into the soil. the plants uses some, some leaches away. how fast the NPK is available / leaches depends on the NPK source. which is why the organic crowd goes with the manure bit - sits there, releases 'slowly' over weeks.
pellets of Miracle Grow 30-30-30 tossed on the surface work fast; and probably leach away in a couple days - perhaps stretched to 2 weeks - depending on how much water / irrigation / rain / slope / run-off is "involved" in your specific situation.
all of the above serves to discount the "burst then starve" theory. there's no even chem-to-the-max fertilizer I'm aware of that "disappears" in 24 hours - so if you've got plants in dirt, daily fertilizing is not indicated.
admittedly, this is a very complex question involving a lot of factors - the hydroponic crowd feeds constantly - why? because the roots are not in soil - and the nutrient mix drains away.