What is the Best Fertilizer for Seedlings?

I've been on a mission to find the best fertilizer for my seedlings. This video covers the experiment I set up to test what the best fertilizer for seedlings might be. I tested 8 fertilizers and 1 bio-stimulant, to see which gave me the healthiest, most robust cauliflower seedlings with the best root systems.
Brassica Guide, which includes a visual reference for nutrient deficiencies in brassicas: horticulture.ahdb.org.uk/know...
Seed Starting Playlist: • Seed Starting
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North Spore Premium Mushroom Starting Supplies (use my code GROWFULLY for 10% off):
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Dripworks Irrigation: www.dripworks.com/?ref=Growfully
Omlet Chicken Coops and Supplies: www.omlet.us/shop/chicken_kee...
A.M. Leonard Horticultural Tool & Supply: amleo.idevaffiliate.com/184.html
Growfully Amazon Storefront (products I use): www.amazon.com/shop/growfully...
00:00 Intro
00:43 How I set up my seedling fertilizer experiment
04:43 The fertilizers I used
13:49 The RESULTS!!
21:48 Thoughts on the seedling fertilizer experiment

[@drleucine]

Jenna, I just love your experiments. I have spent years in research, and I appreciate that you always think about possible confounding factors and controls and then explain them to your audience. I get such a kick out of it! 😊

[@Fireinthesky67]

Same here. She's great. 👍

[@GrowfullywithJenna]

Thanks so much!!

[@pamelalaiosa6638]

I really enjoyed this research you shared!

[@evelynbishop9382]

Thank you for taking the time to do this experiment. I'm with you on not using Moracle-Gro. I have Agrothrive already, so thank you again!😍

[@jhonkrawczun9552]

⁸⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷7⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷7⁷⁷⁷⁷⁷⁷⁷⁷7⁷⁷⁷⁷7⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷⁷7⁷⁷⁷⁷⁷⁷7⁷

[@user-up4ud3kp7w]

Holy cow, I found myself hanging on every word! I always get stuck on what to use for fertilizer. With so many to choose from and seeing you take the time to do that experiment helps so many of us out that either can’t do that or are afraid to. Thank you

[@GrowfullywithJenna]

There are SO many to choose from-- I got overwhelmed trying to decide!! But I really enjoy testing stuff like this, so I'm glad it helps others!

[@Leelongostyle]

Great video. I appreciate the fact that you did not use music in the background to compete with your valuable information. Also, the fact that you don’t keep saying “you guys”. I try so hard and I always overwater and have the worst seedling luck. Thank you.

[@Patriotsoul]

I second that.

[@barryganslein986]

So I’ve started my own experiment, I’ve switched half my seedlings from Espoma to AgroThrive, there is definitely a difference with AgroThrive. Thank you Jenna!

[@MiaTheTherian]

hey so I'm from Australia and I was wondering where you got the agrothrive?

[@joehannan1687]

Absolute LEGEND of a video wow THANK YOU for doing this, 2 years into agrothrive by the 5 gallon pail as a market farmer and I wouldn't use anything else. Stay blessed 🤘🇺🇸✌️

[@GrowfullywithJenna]

Thank you!!

[@joehannan1687]

@@GrowfullywithJenna 🤙🇺🇸✌️💙

[@dustyflats3832]

Good to know!

[@theteenagegardener]

This video could not have come at a better time. I’m wasn’t sure what fertilizer to use to fertilize my seedlings, but now I know! Thank you!

[@GrowfullywithJenna]

Glad I could help!

[@tgif1207]

So, AgroThrive for the win in seed starting. Do you also recommend the brand for regular fertilizing schedule throughout growing season?

[@zanna9857]

Oh my gosh! Finally!! I'm in zone 6b!!! I just saw where you are in another video. I'm so tired of sandy soil, southern ca channels! I need a channel w/clay soil, snow storms in march & the perpetual cloud of sadness! 😂 I'm in NE Ohio & the beach is my backyard. Im having a hellava time! Can't wait to dive into your episodes! 💞💞

[@Babs-Veterans-are-Family]

I'm in Eastern Washington hardpan soil can double as concrete snow storms in March last year it snowed on Easter. Desert sun and dry summers.

[@GrowfullywithJenna]

Well I've definitely got the clay soil, snow storms in March (and April) AND the perpetual cloud of sadness 😆... I'm glad you're here!!

[@dustyflats3832]

😂and sandy desert micro climate with severe drought in WI, with the added snowstorms and long dragged out spring depression and late freak frosts. I know, all the vids of people who can grow year round 😅.

[@Babs-Veterans-are-Family]

@dustyflats3832 those who can grow year round miss the beauty and joy of snow. Sure snow is cold don't want to be outside people drive like they're in bumper cars but is beautiful to watch fall and something magical when you get a white Christmas. It's raining hard gloomy sky my Shiba Inu's don't want to go outside. Wish the weather would play nice so we could get the garden spot prepped. 3 months we'll gripe about it being too hot. Thanks for the welcome.

[@looneygardener]

Southern Ontario here! We just finished winter 3.0, now Fake Spring #2

[@ThriveGarden]

Great work, Jenna! Keep it up

[@susiescott661]

I loved this video. Thanks for taking the time to lay this out!

[@tbluemel]

Another BRILLIANT video!! Keep up the great work, Jenna! Love your channel!

[@shellisspace]

Another massively informative video. Thank you

[@fuzzyfultz]

This was awesome. I shared this to many on a gardening page on FB. Thank you very much. Very enjoyable and informative.

[@pennygarcia3039]

Great video! Thanks for the effort you put in. Very informative!

[@SeedSowr2]

Hi, I would love to see a test on Alaska fish emulsion. Thank you for doing this test, very interesting. You are a good teacher.

[@GrowfullywithJenna]

Hoping to try this one out-- lots of folks seem to like it!

[@dustyflats3832]

@@GrowfullywithJennait stinks! Guard your garden from coon and skunk and inside-either you or the seedlings will be moving out😂.

[@debbiegibson6113]

Wow great test, looking forward to down the road results.

[@AQTGirly4U]

Wow...great video! Thanks for such great information!!!

[@halinapeltonen1777]

You have a great way of presenting- I learned a lot. Loved the details of the products you used and explaining your process. Thank you very much.

[@teresarubel2182]

I was nerding out on this posting. Very helpful, thanks.

[@GrowfullywithJenna]

Great to hear!

[@donnaallred7068]

Excellent video and information. Looking forward to part 2 with the summer seedlings. Thank you for sharing and helping us grow. 🌻

[@studiomcfly6262]

What a helpful segment, I definitely will give it a try especially with my fave brassica, broccoli. I'm not a fan of Miracle -Gro as well but have heard a lot of good reviews on Happy Frog products.Glad I stumbled upon yr vlog, Happy Growing, Jenna!

[@NanaSuze77]

EXELENT experiment Jenna. Thank you!

[@GrowfullywithJenna]

Glad you liked it!

[@darlenesmiles406]

I just found ur channel and i think you and your experiment were AMAZING! I have subscribed and I look forward to watching prior and future videos! THANK YOU FOR ALL YOUR TIME! ~~KEEP SMILING!!

[@GrowfullywithJenna]

Thank you!!

[@NinaHansen2008]

Thank you, Jenna. I really appreciate your test!

[@GrowfullywithJenna]

You're welcome!

[@laurenwilliams3296]

I appreciate your time to get this info out there 😊

[@GrowfullywithJenna]

Thank you so much!

[@stevekroes9502]

Thank you! I appreciate your careful experimentation. I've got seedlings now, and I need to pick up some fertilizer for them, so this is great!

[@kantemirovskaya1lightninga30]

Love these videos! Just came in from planting seeds all afternoon and look, you posted a new video!!!

[@GrowfullywithJenna]

I'm glad to hear you were out planting seeds all afternoon!

[@amyd3464]

Thanks for doing the leg/root work! 👍

[@Aphidman1]

Fantastic. I look forward to the next trial!!

[@GrowfullywithJenna]

Me too!

[@user-hz7kv6js6l]

I loved your experiment. Thank you for the results.

[@GrowfullywithJenna]

I'm glad you liked it!

[@frankporterfield8121]

Thanks for doing this. A lot of great information.

[@user-um7jg6tr5v]

It's so great to find a channel from my zone 6b! It was so cold and snowy today, but i decided to brave the elements and put in my bare root irises. Can't wait for when the weather's consistent enough for everything to go out into the garden.

[@dariagoetsch9132]

Loved this video, adding it to my favorites list. Will be trying out a few of your top contender fertilizers soon.

[@GrowfullywithJenna]

Glad you loved it!

[@katrinagarland5219]

This experiments was great! Thanks so much!!!

[@goldierocks.]

What a terrific video!! Thank you for putting this together. You are a wonderful teacher. I can’t believe those monstrous Agro-Thrive seedlings 😮 Gotta get some of that. 👏🏼

[@tbone9194]

What a great idea. THANK YOU so much for doing this comparing test.

[@GrowfullywithJenna]

You're welcome!

[@tarawatterson4188]

Agreed with these comments - legendary experiment and video. You rock, Jenna! 👊

[@GrowfullywithJenna]

Thank you!

[@benjaminh.7698]

Thank you for the incredible videos you recently shared. 🌟 Your content is not only educational but also captivating, and I find myself eagerly awaiting each new upload. Thank you for your dedication, passion, and the valuable insights you provide. Your videos have enriched my understanding and sparked my curiosity. Keep up the fantastic work! Sending you warm wishes and looking forward to more enlightening content from you. 🙌

[@GrowfullywithJenna]

Wow- thank you so much!!

[@debbieflango2180]

Thanks for the extensive research, time and money in conducting this experiment- I certainly appreciated it and will be altering my plant fertilizer as appropriate.

[@GrowfullywithJenna]

You're welcome!

[@sn232]

I have come back to this video multiple times...thank you for being so detail oriented!

[@GrowfullywithJenna]

I'm so glad!

[@stevefabian-ud2it]

Hi Jenna, Another interesting video. Definitely surprised at some of the results. Keep up the informative videos !

[@GrowfullywithJenna]

Thank you!

[@lesliescully3544]

Super informative and helpful.

[@patrickschooley3503]

Absolutely great video. Very valuable information.

[@GrowfullywithJenna]

Glad it was helpful!

[@beufordjustice4949]

Thank you Jenna for all of the great information you provide; it has helped me immensely in my gardening in both growing and organizing my garden. This video was very informative and I appreciate all of the effort you put forth to complete your testing videos. You are by far my favorite gardening info provider; It makes my day better when I see you have dropped a new video. Take care!

[@GrowfullywithJenna]

It's so nice to hear this- thank you!

[@sn232]

Wow!!! Huge difference, thank you!

[@Too-Young557]

I’ve been using Argo Thrive for a couple years but never on my seedlings. I’ll use it this year. Thank you, this is great

[@Sunnylane02174]

I may have to try that AgroThrive fertilizer bc those seedlings look amazing! Thanks for all you do! You have some of my favorite gardening channels on here! Always so informative!

[@GrowfullywithJenna]

So nice to hear this!

[@andrewmckinley6571]

Thank you for saving me money, was just looking at the fox farm product today. So happy to have found your channel

[@GrowfullywithJenna]

I think the particular Fox Farm formulation I used could be helpful when mixed with other fertilizer- but as a stand-alone for seedlings it's not enough!

[@twirlingswirlinggirl]

So informative! Thanks for helping me as an average gardener get better results with my seedlings. Last year I used Neptune's Harvest with my seedlings and they seemed to do well but I was really impressed by the differences you found between these 9+ fertilizers. I'll keep my eye open for the AgroThrive or Dr. Earth products in Southern Ontario.

[@GrowCookPreserveWithKellyDawn]

This was absolutely wonderful. Thank you so much--I just placed a new Amazon order! Thanks, Jenna. We owe you for all the time and effort you put into this one.

[@GrowfullywithJenna]

I'm so glad it helped!

[@margaret2222]

I love your experiments Jenna. Looking forward to the tomato experiment also. Thanks for another great video.

[@GrowfullywithJenna]

Thanks for watching!

[@laurenholladay]

Thanks Jenna! This experiment was very helpful. I appreciate the time you take to help educate us, especially someone like me who is only in their year of gardening. You're a real blessing.

[@GrowfullywithJenna]

I'm so glad!

[@windriderfarm]

This is such a valuable video. You have saved so many of us time and money. Thank you.

[@GrowfullywithJenna]

Glad it was helpful!

[@wesh388]

Very nice experiment, thanks for sharing!

[@GrowfullywithJenna]

Thank you! Cheers!

[@bigcat5230]

I first found your channel looking up challot tips and alot of good info here thanks for the advice and good channel

[@marthabourassa7909]

I absolutely love your videos! I could listen to you for hours and, quite frankly, have. I just completed a “Growfully with Jenna” marathon. I learn so much from you. Thank you so much.

[@GrowfullywithJenna]

Wow, thank you!

[@midwestribeye7820]

This was a great video! Thank you!

[@jenniferwalters579]

My seedlings are nowhere near this. I need to analyze the starter and now I’m convinced I need an early fertilization before transplanting! Thank you!

[@roxannern9393]

Great information! Thanks for sharing.

[@user-eu9bk7xq4t]

Nice work! Thank you.

[@DDiamondRRuby]

Thanks for trying all the different products, even the synthetic an stinky ones! Hope you and your family are safe after seeing there were tornados in OH.

[@GrowfullywithJenna]

Thank you- we were very lucky and managed to be right in between two of the storm paths where tornadoes formed.

[@PorchGardeningWithPassion]

Excellent video full of valuable details 👊🏻🌻👊🏻

[@GrowfullywithJenna]

Glad you enjoyed it

[@pattiethompson9154]

I came upon your video 2 wks after. Thank you for your time. I started my seeds with just starting soil and water in my mini green house. Didnt realize i could use vertilizers on them until they went in the ground. I am in zone 10 so my planting time is now. I have been busy. New subscriber.❤

[@Crystalspets]

This is great information I was too scared to fertilize my seedlings now that I watched your video for the first time I may have to try this awesome share

[@elizabethwhite7733]

Thank you so much for doing these experiments! I would really appreciate more experiments that would include Jack's 20-20-20 and Spray & Grow products.

[@GrowfullywithJenna]

I'll add these to my list- thank you!

[@helenmcclellan452]

Thank you for taking the time to test diffetent fertilizer to help us select the best product.

[@GrowfullywithJenna]

It's my pleasure

[@josienic361]

Hi you used the wrong foxfarm product....you needed "grow big"@@GrowfullywithJenna

[@Pedeebrotherslawncare]

Jenna, you are a breath of fresh air. Thanks for doing the smart work for us so we don’t have to. Agrothrive is on my shopping list.

[@GrowfullywithJenna]

Thank you!

[@davidhazelton8327]

Excellent reporting! Thank you.

[@GrowfullywithJenna]

Glad you think so!

[@rocky_till]

This was a very timely video as I tried to figure out why many my early seedlings withered away. Initial results in coir starting medium were great with high germination and strong developing roots. I started light fertilization with MG Quick Start, and everything went downhill. I couldn't believe how poorly the root systems had developed, after such a promising start. I had plucked a bunch of extra sprouts early in the process (with very healthy roots), repotted in separate containers, and watched those seedlings perform much better (without fertilization). Your thorough and informative experiment definitely shed some light on my issues. Thanks. Still time to regroup!

[@ronniebrace2917]

Excellent video! Thank you so much!

[@user-wd7vw7zp8e]

Great video as usual. Been gardening for over 60 years, and always happy to learn more. I have been bottom watering my seedlings with half strength Neptune's Harvest Fish and Seaweed (2-3-1), and have had very good results. Odor not too bad, but NOT perfume! Would love to see a comparison of this with your winners.

[@sammyboyde6489]

Great rundown Jenna, people really needed to see this and the differences. ALLOT of work! Where did you get those 10 cell trays? They look really easy to extract from.

[@Naddrose]

Thank you Jenna, what an awesome experiment. You are saving us from seedlings heartaches.

[@GrowfullywithJenna]

You're welcome! I just wish I could test ALL the fertilizers to give a really comprehensive look at the topic... there are just too many on the market!

[@brianczuhai8909]

@@GrowfullywithJenna You should have a tip jar on YT and ask for contributions. Those organics are expensive. And there's way, way, too much stuff out there. I just started a just few more liquid organics last year. And LOVE THEM!

[@elpinchechingon]

Love you experiments!💯💯💯

[@asjanca]

I love when you do these research videos! I panicked a bit when I saw how badly Espoma did since that’s what I’ve been using, but a check of my seedlings confirmed the roots were abundant and healthy. So hopefully it just didn’t jive with your seed starting mix. Fingers crossed! 🤞🏼

[@GrowfullywithJenna]

I'm starting to think I had a bad batch of Espoma-- I want to buy a new one to test!

[@tgif1207]

Yeah, that one result was a bit shocking for sure. I also wonder if Jobes might have done better if the middle application hadn't been skipped. Or if it had been mixed in with the coir at the start.

[@jedpusczykowski4955]

I got that Agrothrive over the weekend and it seems to be doing awsome for my seedlings and plants. That you so much!!!

[@GrowfullywithJenna]

Glad to hear it!

[@user-gk8es5sv3m]

thank you for experimenting for me. I have been on hunt for seedling fertilizer. Great luck for me as yesterday I just ordered the Argo brand for my seedling plants. Thanks again for your advice and information. 😃🌞

[@GrowfullywithJenna]

I hope you have great results!

[@matthewjc89]

I LOVE garden experiments!!! Thank you so much Jenna! It's why I keep coming back! If Jobe's did that well just as a top dressing, I wonder how much better it would have been mixed into the soil where it would be more available to the roots?? Would love to see that! :)

[@GrowfullywithJenna]

I'm thinking I'll have to actually follow the directions next time and see if it makes a difference!

[@tonipollack5021]

I would like to see another test with REV using the actual recommended directions since it isn’t an actual fertilizer. Love your channel.

[@foodforestretirement2799]

Wow! I wonder too about using a different growing medium because that had some unexpected results. Nice experiment for sure 👌 Thank you 😊

[@margaretodea7633]

Excellent vidéo. Thank you for this experiment.

[@GrowfullywithJenna]

Thank you!

[@mygardenofthings]

Amazing job! Thank you!

[@shannonsantana2439]

So fabulous! Thank you!

[@tater357]

Great test. Thank you.

[@GrowfullywithJenna]

Thanks!

[@brianseybert192]

This just goes to show, throwing money at plants does not always work. Really enjoy when you present real world comparisons of commonly used products. Me personally, I will stick to my homemade compost and worm casting extracts, it is free, just a bit of labor. I did purchase a bag of EndoBoost Pro Mycorrhizal Fungi, I used mycorrhizal fungi in my potting mixes a few years ago and I did see a difference. Nice experiment, a lot of good information. Thanks for all the work you put into it. Stay Well!!!

[@FC2ESWS]

I subscribed to see the next experiment. I was totally going to recommend repeating the same with another crop like tomato or cucumbers. Great job.

[@GrowfullywithJenna]

Tomatoes are in the works! And thanks for subbing!

[@kirstmlarson1]

I used the AgroThrive all purpose last year and repurchased a couple gallons for this year. It was so easy to use, and forgiving if I was mixing up a big bucket outdoors. I never had issues with burning plants or even when it was applied at noon by one of my kids rushing through one of “mom’s garden chores”.

[@zaria5785]

I really appreciate your honesty and sharing that you didn’t want Miracle Grow to be as successful. 😂 I was a bit surprised honestly. Your explanation that perhaps the salts in the coconut coir may have inhibited nutrient uptake was not something I even thought of. Thank you so much! Now I know what to spend my money on. I’ve tried Espoma for citrus and avocado blend and honestly I feel like my worm castings and home compost provided my orange tree with more healthy growth.

[@teenadamron7654]

Love, Love, Love your videos!!

[@GrowfullywithJenna]

Yay! Thank you!

[@brokenmeats5928]

I love ALL Growfully with Jenna videos!

[@GrowfullywithJenna]

Thank you 💚

[@tomcox5063]

This was really a great video. I used the Espoma grow on my starts last year and had spectacular results. I must admit I have concerns now as it’s time to start fertilizing my starts again. Thanks for sharing this I really appreciate it.

[@TheJackeeeo]

Same. Had excellent results with Espoma. I'm assuming it's the growing medium. I use Sun Gold seed starting mix, plants went crazy!

[@GrowfullywithJenna]

I'm completely confounded by the Espoma results. I'll definitely be testing that one again!

[@michellelee8140]

I dont comment, but u literally just saved my very first season. Youre an angel 🙏 thank youuuuuuuuu so much!! I cant say it enough

[@GrowfullywithJenna]

Glad I could help!

[@thatzmyart675]

Thanks for the results

[@noraalvarado8178]

What a great experiment. Always love your videos. I started my cabbage and broccoli seeds on February 23rd in jiffy peat pods . After they get maybe around 2 inches I unwrap the pod and repot them in miracle grow potting soil. We've had a warm week here in N.Y so I planted them out last week because they were as big as yours seedlings that you used the Dr Earth with. I have not fertilized them at all. Just threw some blood meal in the hole when I planted them out. Next week only in the 40s for the high opposed to the 50s and 60s we had last week. Can't wait to see your tomatoe comparison. I start my tomatoe seeds the same way and do the same as my cabbage and broccoli.

[@GrowfullywithJenna]

Thanks so much

[@freedom_born]

Whoa. Just finished the video. That was freaking awesome: Contenders: NPK ratios: Smell test: Grow test: Root test: Results and Opinions: Mind blowing setup. Honestly, that was a bloody bonzer experiment. Poor MG still not shown any love (rightfully so 😅), and geez did the results speak volumes. Yucky stuff. I'm still processing your results. Sincerely appreciate the transparency too btw. Thank you again Jen. Well done mate, awesome topic and content.

[@clarityquester1653]

nicely done!

[@GrowfullywithJenna]

Thanks!

[@johnnyearliwine6698]

Really enjoyed your exp.. I am always wondering what fertilizer is best. I like to grow tomatoes, peppers, and cucumbers. I will definitely follow your findings and techniques . thank you.

[@cinedan5497]

You should have used the Fox Farm Veg bottle, not the bloom. Those babies need their Nitrogen! Otherwise great info.....thanks for this experiment! I'm definitely going to try one of the top 2 this year.

[@mala4027]

Excellent video!

[@GrowfullywithJenna]

Thanks!

[@jrdoolin]

First of all, I think your experiments are one of the best parts of your channel. This one was fascinating. Keep them coming! Second, holy smokes, I've been using Agrothrive as my primary water soluble fertilizer in the garden, but I never thought of using it for seedlings. But I sure am sold now! Lastly, I actually use diluted synthetic fertilizer for my seedlings and they are doing really well. It's something like 1/8 tsp in a whole gallon of water. I'm also using ProMix for the medium, though last year it was coco coir and I didn't get the negative results that you did with Miracle Gro, so perhaps it's the concentration.

[@GrowfullywithJenna]

Thank you! And I do know lots of folks use synthetics (especially on those indoor seedlings) with good results. I think I'm going to just test a different synthetic product next time.

[@kennethhigby1723]

I'm excited to learn from you. I'm a disabled veteran who has a ranch on the little Redonda Mesa in Apache County Arizona. This is our agricultural development year we will be planting thousands of seeds. Thanks for the update. This project is the earthship build project for disabled veterans.

[@GrowfullywithJenna]

What an amazing project!!