When + When NOT to Use a Heat Mat and Humidity Dome For Seed Starting

Heat mats and humidity domes can be a beneficial resource for seed starting, but there are specific times to use them and when not to use them. In this video we will break down the risks and benefits to using a heat mat.
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[@jeannamcgregor9967]

Hah! I use my heat mat all year long but not necessarily for seeds. Heat mats are brilliant for encouraging sourdough starter and on bread day for the dough itself. 😊

[@karenm5681]

Oh! Never thought of that! Good tip, thanks!

[@sarahcourtney1658]

Great tip! I made bread yesterday & I`ve used a heating pad from 1973 to proof bread. Now if it quits on me..I know what to use!

[@tonyavernon]

brilliant!

[@Impulse_Photography]

So is cooked pasta water - I always use it to make sour dough starter ...

[@karenm5681]

@@Impulse_Photography Cooked pasta water…do you mean store-bought pasta or homemade pasta, made with flour & eggs etc?

[@bethwestfall2238]

I was listening to this video today while driving and literally made a doughnut on the mainstreet to get home in time to save my seedlings from all my mistakes 🤯 - Thank you for all these informative videos!!

[@juliekadams]

Yeah, I have broccoli in with all the other plants that DO need the heat mat, but they are ancient seeds that are probably not viable anyhow. If any of the 4 sprout, I'll be pleasantly delighted, LOL.

[@lindamcknight4790]

😂

[@Oktopia]

I germinate my seeds in used fast food containers with lids. The lids come with flaps to open so air can escape/circulate. I adore this setup because the minute the seedling pokes up I remove the lids and water from underneath. Been doing this for a few years now with excellent results.

[@tretre1692]

And it helps with the landfill issue a little! Depending on how long you use them! Good idea!

[@joesqudy]

I do that too

[@jdawg1835]

The recent public health scare has left us with an over abundance of these plastic trays at home. We are repurposing these as well. Great idea.

[@kuganescollins8563]

Are they under grow lights.

[@starladoak7276]

@@Jbtpba spray paint them.

[@stellaluuk2713]

I decided to try sowing lettuce outside in early March with snow still on the ground in a raised bed, here in Ontario, Canada zone 5b. The result was early lettuce and it didn't bolt until August. Then I saved seeds from it.

[@Andre.K.]

Direct method :)

[@jkplester8917]

Hey that's awesome! I'm in BC, zone 6b - I wonder if I should try that? My only real issue is the fact that I don't really have any place to plant them. LOL! No garden beds. Maybe next year.

[@michaelsherron5750]

What I learned today: 1) warm weather crops prefer the heat mat and cold weather crops do not want it. 2) Don't wait until all seeds have sprouted before removing the humidity dome. Remove the dome after I see my first sprouts, otherwise I risk legginess in the stems and gray mold. [ and I have had both when growing microgreens] Thanks! 😃

[@penelopegrier5073]

Right. The second one here has always been a big one for me. I had heard in more than one place to leave it domed until most, if not all, the seeds have sprouted.

[@theresacougler5937]

I retired last year and have a renewed interest in gardening. I am so happy that I’ve found your channel. Your videos are always enlightening. I struggled last year with starting plants but with your advice hope to be more successful this year.

[@terrygreenlee7702]

I always enjoy n learn new things

[@suzyqakers2418]

We retired a couple years ago right about Covid time and have gardened for over 40 years. Now it’s a complete educational new adventure. Every year’s a different challenge and education. One by one we equip ourselves with not only the skills but also the ‘armor’ against so many battles. For instance last year’s surprise battle was flea beetles. Right now I am on the homestretch with indoor fungus gnats. And there’s the powdery mildew. Finally I am understanding and being successful. Thanks to Luke and others’. And I save seeds.

[@TacoBell5DollarBox]

retirement? LOL you must work for a city. There's not a chance a non union worker is retiring. I wish I could garden all day!

[@AmysAttitude]

​@TacoBell5DollarBox People retire all the time, daily. It doesn't matter what your job is or where you live but it does matter how much effort you put into your job to begin with. Sounds like you're the no effort type.

[@amommalee9105]

Just sharing my tip. Clear plastic egg containers work really well for me. Each egg cell can be a different plant, you just need to map it on paper. Keep the top, that is your dome. After sprouting, you can spoon out the seedling for transplanting into a room temp pot without disturbing the roots. Of course this won't work with large seedlings like squash, but it is perfect for herb seeds and peppers. Depending on your mat, you may need to have a towel or 2 between the mat and egg crate. Always use boiling water to wet your soil mix, this will kill fungus gnats and mold spores. Let it cool sufficiently before you plant. I will get algae growing in cells if it is left too long, but no mold or gnats.

[@sarahmcenhill]

Won't the bowling water kill the mycorrhizae in the soil?

[@amommalee9105]

@@sarahmcenhill By soil mix, I mean seedling mix, it should not have any microrhyzae added. However if you only have potting soil to work with that does have it added, then I would still boil it when you are starting seeds. Yes, you will kill that too, but since you are eventually going to transplant later, you can move it into the regular potting mix later.

[@Kenzingo]

Eh. Just quarantine the plans from any plants you currently have going at the time and use mosquito bits in your watering regimen.

[@Kenzingo]

People don’t realize how important fungus is

[@marydiscuillo142]

I ran over and shut off the heat pads immediately. Omg! Killing w kindness. Thank you Luke!!!!!!!!

[@maryannepreston4685]

Thanks for explaining this in layman's terms- You are a good teacher!!

[@conradkappel9426]

Finally an excellent discussion on heat mats and humidity domes. I'm not aware of any other videos that discuss these dos and don'ts. That's kind of amazing when one considers the importance of this subject. Thanks!

[@milenameguerditchian5854]

This was super helpful. Thanks Luke!! Could you also tell us about how and when to use grow lamps and indoor greenhouses? I live in Utah so it’s dry and cold here. This is my first year starting my garden all from seed.

[@lukeyland9594]

Dude your videos through out the years have helped me grow my business. Out of all the farming channels you are my go to for detailed, yet simple to follow vids. Thanks

[@scottboyd9383]

Dude? .....how old are you? show the man some respect. dont call him dude

[@simpinainteasyRHEC]

​@@scottboyd9383 dude, why you acting like such a little immature girl? Scott, my dude, get a grip.

[@denisecolvin4667]

@@scottboyd9383Mr. Dude, please be aware that on social media dude, chick, man and yo are all terms of respect/endearment when followed by a compliment. Bless your heart. I hope you have a great day.

[@chuckwaardenburg496]

​@@scottboyd9383 Come on now, good sir, if you listen to yourself, you sound like a grumpy old man. If you can somehow get over your shock, read past the dude part. It's quite obvious he is paying the man the upmost respect and praise by saying he's better than all the other channels. That in fact he has helped his livelihood. It appears a few other people agree with his view and nobody else finds it offensive or disrespectful but yourself. Now good day🖖

[@gabrielanthonio5325]

@@scottboyd9383 Mr. Boyd! It's delightful to see a man with such manners in todays day and age. It is a rather rare occurrence. So I hereby salute you for your foolish efforts to make people of such low caliber speak like yourself. I admire you taking your time to speak to the peasants in this commentary section. They clearly should know to behave better. *Sarcasm* 🤫

[@philipclift7205]

What is this florida? Canada 🇨🇦 we do it different. A 40 watt lightbulb in a storage container warms the lid, which is now a heat mat.

[@undertheblood31]

What about herbs like thyme and rosemary would a heat mat be beneficial?

[@anneishaseaton3186]

I'd like to know this too.

[@debracrow9656]

I know to remove the heat dome when seeds begin to sprout but do you remove the heat mat when all seed are sprouted or when you see just a few seedlings?

[@MIgardener]

when a few have sprouted, the heat mat comes off too.

[@debracrow9656]

@@MIgardener thanks

[@sherylholder7703]

I am learning so much!!!! I bought heat mats last year. Yes I used them after germination and yeah the plants were a failure, but now I understand why!! I also learned fr your viewers to use the heat mats to help my sourdough stater get going. My house is usually 65-68 degrees. I have a heck of a time. So much great information!!! ❤❤❤❤

[@preschoolhomestead]

Thank you for addressing humidity domes, it was very informational. I was shocked when you didn't say, "Grow big or go home!"

[@ca-if1cf]

Thanks so much for explaining this so thoroughly Luke, your videos have taught me so much!! I've been trying for years with very limited success to start from seed indoors. This helps. I haw a feeling its going to be a good year in my garden!

[@dumbbunnie123]

I just watched a video of yours that is about 7 years old. In this video you raved on and on over a tomato called orange rue cellini(sp)...I went on line and couldn't find it...do you still have the seeds? I d like to buy some.

[@ChristinesBackyardGarden]

I'm glad I saw this video because I just bought a heat mat and was going to place it under my plants (lettuce, kale, broccoli, etc) and some already developed leaves.

[@clb50]

I love you and your channel but every time I hear your intro it reminds me of a cassette tape that is getting eaten in the car stereo. 😂 Yes I just dated myself. All good as your content is some of THE BEST. Period.

[@northyland1157]

I been growing lettuce and onions outside all winter.. Don't need a heat mat! For my peppers, Yes use a heat mat!!! Another thing to look at is the overnight low temps. Cucumbers need it to stay above 55 at night, or they refuse to grow, and may even die! Do a little research on the plants you grow, and your garden will thank you...

[@retiredinnameonly8429]

thank you for explaining how to use domes. i never use heat mats, but I can see where I've gone wrong with the domes. I used to leave them until my seedling tomatoes touched the top. Oppps. The only way I have avoided fungus and such was the cinnamon I sprinkled on the soil as soon as I seeding.

[@beth4775]

Woke up this morning to 6 out of 20, of your Alexandria Strawberry seed,sticking their little green leaf heads up! First time trying to grow Strawberries from seed, thank you for your fantastic seeds!!!

[@gaj1490]

You should go to Charles dowdings account on KZbin you may learn a thing or two about muti sowing in tiny seed trays no growlitghts required full veg plots all year round with no digging.

[@lisagee2789]

Luke, I noticed you made this video with your knee on the floor . You can raise the legs on your table and buy a stool to adjust to the appropriate height so you can comfortably sit when you start seeds in videos. Twenty years from now your knees and back will thank you. Gardeners should consider incorporating ergonomics practices while you are still limber. I thought you made a video on this somewhat recently👨‍🔧❤‍🩹🍈

[@cliffordpayne4795]

90% of my tomatoes germinated, but only 1 bell pepper germinated. These are all brand new seeds.

[@wvnanaskitchenandgarden]

Do you have to use the humidity dome if using an indoor greenhouse shelf? I have heat mats but am not using the domes currently.

[@rg-mi5hh]

Good information. We have been wintersowing in milkjugs in our breezeway for a couple of years. We also got a tiny grow light to grow a few tomatoes inside. Can't wait to see it with grow light.

[@Fred.pSonic]

Second year grower and yeah I left the mat and humidity domes on too long. Also had the green mold on top of the soil from too much moisture, every rookie mistake made. I know that improper lighting technique can cause legginess but I wonder if too long on the mat also contributed to the lengthy gams I ended up with. Not a total seed-starting failure but lost quite a few by not being more careful. Just starting up again in the PNW, thanks for the timely tips Luke.

[@laurenholladay]

I just did the same thing last week. Now all of my brassicas are leggy and falling over. So now the heat mat and humidity domes are off and Monday, I'll transplant them outside. What a goof ball I am! rookie mistakes like you said :)

[@sweettalk9200]

How to prevent the green mold on top

[@victorrosas-br7fs]

@@sweettalk9200 maybe don't allow it to be wet so much allow it to air off some to touch

[@myhusbandsrib]

I did exactly what u said for the braccias and they are supper leggy! What now

[@bettypearson5570]

Basic household temperatures in the winter are recommended to be 68° in winter. If you have been outside where it is32° it is not only going to feel much warmer than outside that difference of 7° between 68° and 75° will save you 14-21% on your heating costs. Additionally, having indoor temperature of 72 and higher is a great incubation temperature for viruses and bacterias trapped indoors meaning you and your family will be more susceptible to becoming sick in the winter. And then there are those sicko people like myself who prefer the temp between 55°-60° who do need the heat mats for most germination although I think I have been misusing the domes. Love all the info.

[@jackjohnson291]

You’re not a sicko-you’re perfect. Married? 😆 I too keep it very cool. If it were practical, I’d keep it that way year round.

[@bettypearson5570]

@@jackjohnson291 not married but probably way too old.😘 But hey, if you have good night vision and can do chores on a ladder without getting dizzy you could be pretty perfect yourself.

[@noraalvarado8178]

Great information, i don't have a heat mat. I use the top of my hot water tank in my furnace room and had great success with my tomatoes last year and with my sweet potatoe slips that I do the potting soil method with.

[@craighalle7892]

I use those carry out containers to start plants, too. Those large trays haven't worked well for me. I got the idea from Growing a Greener World, Craig, the tomato expert, who starts many seeds in small trays and moves them to 3 inch pots. His name is Craig, so why wouldn't I listen? There is one container I liked but could not use, and that is the rotisserie chicken container from Costco. Even though it seemed like a mini greenhouse, plants did not grow in it. I don't know why, but it's back to the recycling bin. There is one more thing I figured out. When moving from the start container to the 3" pots, I use a small plastic fork to carefully dig the seedlings, which avoids root damage and I use a plastic spoon to press the soil evenly around each transplant. I get the best seed growth this way using heat pads, and when the first ones sprout, I turn off the pads, and they keep on growing and sprouting. Thanks again, Luke, and may the Lord bless you and yours.

[@AJsGreenTopics]

Great information. 😎

[@lizatrue7543]

Question: I live in Colorado...dry climate. I grow microgreens on coconut coir mats in a cheap mini-greenhouse in my family room. In the past I've used heat mats until the seeds sprout, have grow lights on each shelf, and have a small desk fan blowing over 12 hours a day. My question is: I've never grown broccoli microgreens/baby greens, so will they benefit from a cooler environment since they are a cooler weather crop? Ty for your VERY informative videos. Even at 67 years old, I'm learning lots from them!

[@tracycrider7778]

They do! Cooler temperatures

[@Nikki-mx5my]

Yes, no need for heat mat for cooler temp crops. Heat loving plants benefit the most from a heat mat: tomatoes, peppers, eggplants and some herbs. For most micro greens, you likely don’t need a heat mat at all unless you are growing them in a really cool area of your home (such as a room you don’t spend a lot of time in and keep the heat down really low).

[@hai6089]

This is so helpful. I started a practice run with my seed starting kit / LED and they all came out leggy and died. I left the dome on waaaaaay too long and didn’t water them. 🤭😭

[@jdelgadosegovia]

Can you make a video on lighting we can buy at menards like off brand

[@farkadelia6776]

Finally someone with good information on when some of the seedlings have sprouted!!

[@jeffreylangley]

Good Afternoon from a snowy New Hampshire. May the day find all safe and healthy.

[@lorrigierman7089]

Another great video! Really appreciating this seed starting series. Keep up the good work!

[@themelicious7733]

Thank you for the informative video. Total noob here, I may or may not have run into the next room over to shut off my heating mat lol.

[@mompuff]

Thank you so much for the amazing teaching videos!! You are a great teacher & big help!! Blessings to you from Kentucky 🙌🏻🦋🙌🏻

[@TJtheHAWK]

I just use my heat mat for peppers and eggplants. Everything else seems to germinate on its own just fine.

[@mellyg8872]

Yes! I’m getting Spring Fever 🤣🤣 Thanks for this Luke. Now I know what I did wrong last year. I didn’t take the heat mat away.

[@patriciaserdahl5577]

Thanks Luke great information I now know why different seedlings 🌱 didn't do well with my Domes n Heating Mat in the past .Took notes and will definitely try your suggestions 😉

[@adventuresinlifemka1762]

I just re-watched this for information about using the heat mat for my onion seeds. I love being able to watch this great information whenever i need it. Thanks!😊

[@nanaof6babies]

I've watched this 3x now. Did he say to use it for onions? I don't know what to do!

[@anishinaabae]

@@nanaof6babiesuse a heat mat for warm weather crops, and don’t use it for cold weather crops.

[@carolparrish194]

That was useful information. Now when is a grow light necessary and not?

[@Riggersons]

I've used many heat mats over the years but have never seen one that says "this side up" on either surface? Does it matter which side of the mat goes up?

[@COUNTS1096]

Video suggestion: hypothetical- the stores are closed and there’s no way to get a starting mix or anything from the stores. How would you compose a starting mix from the things you have or can be reasonably found in nature.

[@kaitieriley]

Just use homemade high quality sifted compost. Low temperature sterilize if starting indoors.

[@magnolia718]

After gardening for your very first year, you learn to get a bag of seed starter mix and potting mix at the end of the season, ready to start the next year whenever you want to!

[@megantuthill8544]

I was wondering why I was getting really good initial sprouting then everything started stalling or going backwards.. things started dying or looking unhappy... because I was keeping everything on the heat mats and under humidity domes! Now I know better!

[@lindad768]

Thank you for this valuable information. Love your channel! How close do you keep your seedlings to the grow lights? Thank you again.

[@rosebayer114]

Another great video Luke. If my next question has been covered in a previous video, forgive me, but I'm wondering how long a fan should be kept on?

[@MIgardener]

I usually keep the fan on at all times.

[@MIgardener]

I usually keep the fan on at all times.

[@rosebayer114]

@MIgardener Thanks Luke!

[@bonniepetterson3299]

This was so helpful! Thank you! I feel overwhelmed starting a garden because people make it complicated. But you simplify it!

[@dianepless4023]

My question would be, can I continue to grow my seedlings in a 50-degree garage?? (with grow lights, of course) until the weather warms up? I live in Michigan & I would like to get them out of my basement.

[@Chris-zu4es]

I'm in search of a propagator with built in heat mat, lights and underneath watering "system"/mat but it seems hard to find

[@GMT439]

If you have separate domes (which are available) in most small pot sizes then you can remove the domes individually as the seedlings emerge. Also if you germinated in Rockwool minis or Jiffy Coco Pellets then you could remove each plant from the propagator as they emerged too.. What I'm trying to say is your method is not what professional growers do and it's not the equipment they would use. 90% of food is grown in Rockwool in NFT or SLAB Hydro methods., They also grow from cuttings all the time. The seeds are just for finding the mother plants to keep and take clones from.

[@stephenwalczak3166]

I don't know why this kind of bad information about heat mats continues to be spread. If you want a jump start on growing seedlings early in the season, use a heat mat, but always with a thermostat set at around 75F or 24C. This will keep the soil at a constant temperature and stop wild fluctuations that are impossible to control. Not only will this gentle warming increase and quicken germination rates, it will also increase the soil biodiversity which aids in nutrient cycling. As a result you will have stronger roots, thicker leaves and much better growth. To suggest warmth will cause 'leggy' growth is incorrect, this is more likely insufficient and incorrect lighting requirements. Growing seedlings under normal household lights will cause thinner cell walls and overall poor plant health. Thermostat regulated warming will also increase drying of the soil and greatly reduce the likelihood of disease. If you're heating your soil, room humidity levels don't become such a problem. But if you're suffering from dry skin, eyes and throat, then your plants are probably also suffering, so yes you will need to increase the humidity. Hydrometers are very cheap and show constant real time levels, and if you need to increase the humidity in your home, humidifiers are also cheap. For your health and your plants fifty to sixty percent will be fine.

[@davidlillecrapp2960]

45 degrees for lettuce germination, wow that's super hot! . . . Ohhhh you mean 7 degrees not 45 degrees, now I understand! I would never germinate lettuce seeds at 117 ish degrees Fahrenheit. Fahrenheit is almost exclusively an American thing; translations to normal temperatures (ie Celcius) would be appreciated.

[@lunalou3489]

TY!!!!! I have such a hard time with this.

[@nininoona]

My biggest issue with starting seeds indoors is that my house is unnaturally cold during the winter. It's very old and poorly insulated so on very cold days my house's internal temperature is anywhere between 45 to 55 degrees. I bought a heat mat to try this year but I am still trying to figure out how to keep the plants warm overall once they germinate. I've seen a lot of conflicting advice so it's getting a bit frustrating. I have several varieties of tomatoes that I want to grow that I cannot find starts for, so I have to start them from seed myself. Last year, without a mat, they didn't germinate at all so I had to go without. And the ones that did germinate ended up having fungal issues and dying before it got warm enough to plant outside. Any advice on how to best (cheaply) keep them warm overall?

[@Fred.pSonic]

I have a similar situation as I germinate in a cold garage, I assume you're using a baker's rack with proper lighting or similar contained setup. On the really cold days I'll put a light bedspread or blanket over the entire rack to keep all the heat contained making sure there's a crack for airflow. If you're not doing so already get a small oscillating fan and have it blow across your seedlings at the most gentle setting--the fan is important. This will help strengthen the stems and the constant airflow reduces the probability of mold forming and spreading. Grow lights should be only a few inches above your plant. Don't forget hardening off for about a week, super important. Once in the ground don't over-fertilize, better to be under instead of over. Same thing with watering, don't over do it. Okay to be a little dry versus too wet, should feel like a wrung out sponge. Lastly of course choose local variety plants, typically less maintenance and more vigor. Good luck with your grow this year, I know you can do it!

[@nygardenguru]

Start later. I won’t start my tomatoes until April,1st zone 7a . No need to start too early.

[@theresarichards5549]

Our house is also old, and the room I sow seeds in is small, so I bring in a small electric heater and only need to run it about a couple hours a few times/day to warm up the room to 70 degrees. No heat mats.

[@joniboulware1436]

I just elevate the trays above the heat mats a few inches by setting them on whatever is handy small boxes etc . They get indirectly warmer space without hotter soil.

[@Happilymarrieddad]

I've been considering using an old bitcoin miner to generate heat and add airflow to my greenhouse. Not sure if it will work but I might give it a shot this year. Have to run enough power out there though.

[@jeas4980]

Hey Luke, are you still using the trench compost method in your raised beds?

[@martinmercerjr8615]

I keep asking you if my garage is still below 50-40 degrees. Should I keep tomatoes, peppers and cucumbers plants on a heat pad. Because I think my garage is still too cold for these plants

[@matthawkins4579]

Ok...I have a heat mat and a humidity dome. I have a flat of 32 2 inch pots that contain 6 different varieties and species of peppers. Two of the varieties have germinated. Should I pull the dome off or not?

[@LeslieKaster-j5h]

Most everything i see says to prop up the dome until most have germinated, which i have always done. Often for several days, especially for peppers, because they tend to germinate randomly. This year i will try taking the dome and heat mat off earlier than i normally do. And maybe turn the heat mat lower for my peppers and tomatoes. I typically have the thermostat set 82 for those and they pop up in like 4 or 5 days. Maybe i will set them more at 77, 78?

[@lareinademaz]

Does a fan get run 24/7, or only when the light is on in the cycle? Can you use more than 1 fan, and if so should one be oscillating & the other stationary? I understand making the seedlings strong, but don't want it too crazy either & no one ever specifies that I've found....

[@candypodratz]

I need a heat mat to start literally any seeds. Because of my cats, i have to start all my seeds down in my concrete cold basement. It's like 50 degrees down there. Once i get the seeds to germinate, the grow lights seem to be enough to keep them going. But with no heat mat, I'll be waiting until April for my seedlings to pop up. Even if I plant them in January.

[@kittiew260]

Awesome update, really does serve great reminders or knowledge for new gardeners. 😀

[@delynndehardt1859]

I dont understand why Im having failures in germination. Ive started seeds for decades and never had jush problems. I wash the cels & trays in light bleach water every spring. I seed in feb-mar in seed starting medium. I used to use tegular potting soil. I even failed starting zucchini. Around here Zukes are almost a nuisance plant. But I failed starting them. Only in the last 3 years. I dont use heat mats. I bought them, but dont use them since I went solar.

[@Sunnyd137lid]

Fantastic information! One question….if using a heat mat in an unheated area to help keep soil temps warmer….can you leave it on after seed sprouts? And by leave it on I mean use a thermostat set at maybe 60F.

[@martinmercerjr8615]

Using dome in garage, if it’s still very cold in there. If I am growing cucumbers, tomato plants and other warm plants. As soon as you see one or seedlings coming up. Should you take the dome off, even if they are different seedlings

[@Frankie_902]

Luke @MIGardner When the seeds begin to geminate should we remove the tray from the heat mat as well as removing the humidity dome?

[@brokenandcraked]

I wish I would have seen this video two weeks ago. I'm trying to grow tomatoes and peppers from seeds for the first time. So I got a grow light and a heat mat. I jus assumed the heat mat was programmed to only heat to the proper temperature. it's been 12 days since I sowed 60 seeds between the 2 types of plants. I have 6 seedlings. Nothing else germinated. So out of curiosity, I threw a thermometer inside my humidity dome. Ya, those poor seeds have been sitting about 88 to 90 degrees Fahrenheit. So I bought a thermostat for the heat mat, and guess I'm going to be restarting new seeds

[@Kenzingo]

My poor poor hot peppers. 🌶️ I was wondering why they weren’t growing.

[@jimsingleton3790]

Hey Luke I read about a lab made hybrid called rabbage, a cross between a cabbage and a crazy as it sounds a radish. The article said they were really delicious, I think you ate the leaves. But the article said as they disappear from gardens they may never be found in the near future. I would love to grow some to see if they are worth saving. But I can’t find any seeds. Please help me!

[@roygreene2921]

Can't wait to put my plants in the ground thank you for all your valuable information

[@jeffclarke5497]

Even young people are allowed to use active language, as in "people often ask this question" as opposed to "this question gets asked." You might get kicked out of the twit club, but you might begin to sound "like" an intellegent adult.

[@jordanphillips1541]

Thanks for the detailed video. It answered a lot of my questions

[@cscott505]

I'm late but does onions need a heat mat or humidity dome? Im SUPER new and I thought all seeds (when starting indoors) would be started the same! :(

[@phukkelberry2846]

Thats why you start seeds with a seed starter mix, preferably coir, that has no nutritional value. If there's nutrients in the starter mix its just food for bacteria and fungus.

[@bloomingpetals9290]

If they are cold hardy, why cant you start them outside by seed right now. Asking for Zone 8 Seattle? Do all these cold weather plants have to be started inside? Or can any of them be direct sowed?

[@helenkrieger191]

Thank you so much, totally clarified alot for me and the second heat mat I was going to buy- won't be ordered.

[@bonesdoes6142]

A heat mat will raise the temperature around 15-20 degrees. And that’s a bit to inconsistent for me. This is why I use a controller with a temperature probe alongside my heating mat. They’re relatively cheap and super easy to use. The mat plugs into the controller and you adjust the settings to the preferred temperature. And with the humidity dome,it can cause the plants that are sprouted to stunt. Too much humidity and the leaves can’t transpire,and if they can’t do that they can’t take up nutrients and thrive.

[@martinmercerjr8615]

Hello, what if your garage is still cold. Should I use a heat mat and dome for cold weather crops, like Chinese cabbage

[@jokimaguire5045]

Wants the best seed starter😂🎉I've treied heated propagator but in uourpionion what's best, my propagator is not heat control help my seeds are about 10 pound eack

[@tomallison7416]

If I start seeds (cracked with tiny tail) in water/paper towel (anything that precedes the dirt & tray) and then put them in the dirt & tray am I still in that part where I apply heat & dome or do I skip the heat part entirely (it's germinated) and just keep the dome until they break the surface? These are questions that have me up at night

[@suburbanfarms]

how tall should tomatoes be before I put a fan on them?

[@s.barlow7062]

Garden Answer suggests using vermiculite to cover seed starts to keep the seedling from molding.

[@martinmercerjr8615]

How do you treat flower seedlings, should I take them off the heating mat as soon as they sprout. Even if my garage is still cold

[@SC-gl5jx]

Where should the probe be placed in the soil or under they tray? When I placed the probe in the tray with soil the thermostat never shut off. When placed under the tray, it kept the temperature according to the thermostat settings.

[@daddy1571]

I used a heat mat for my seeds and every one of them cooked. It was an expensive lesson. I never use these now. They're not needed.Ridiculous

[@justuslightworkers]

I definitely like my heat mat and humidity domes. My seed starting took off once I added in the heat mat. My peppers (especially), watermelons, squashes, etc. definitely have to have it, my tomatoes and a few other summer veggies like it pretty well. I use the dome for most things, but not peppers, because they don't like "wet feet". Plus my grow table is in a pretty dry spot of our little house. Great info Luke as always!

[@Tlu2000]

What if your humidity dome has grow lights attached to it. How do you handle that? My humidity dome has grow lights and air vents. How do you handle that?

[@chuckezell7614]

Do you have any experience with carnivorous plants and the heat mat humidity dome recommendations?

[@nastytechniquez9685]

One thing about heat mats many don’t know is that the heat will increase evaporation which in turn can increase oxygen levels in soil by causing more air exchange in the soil.

[@gabrielanthonio5325]

In the case of growing Cacti you do not want to take off the humidity dome right away. Some species like it on for a couple of months after sprouting. You need to sterilise the soil for that to work without risking mold though.

[@thegame1185]

question....if I have multi types of tomato or pepper seeds trying to germinate. If some seeds start to sprout well before the others. Should I turn off the heat mat off even those some of the other seeds still haven't germinated yet???

[@j316finewoodworking6]

Ok im kinda new to all this. I don't have heat mats...but where I began growing is in my basement with a woodstove down there. My tomatoes are getting big fast and yet broccoli not a thing. Did they get to hot? My peppers germinated in 3 says. Am I prone to lose them?

[@bobcat9314]

I like a heat mat for seed germination. once I see the sprout..the heat mat is unplugged , sanitized, and put away till next time.. Its worth it to purchase a quality heat mat with temperature control, and a soil thermometer..soil will hold heat..so the soil temp, and heat mat temp may not be the same..