You’vestarted your seeds indoors , witnessedthe trick that is germination , and watched your sprout grow into thin , light-green little seedlings .
You recall they ’ll be ready to figure the public outside the confines of that ardent , intimate house of cards called your kitchen ( or bathroom or glasshouse or wherever they ’ve been shacking up ) in a few workweek .
But like a good parent , you do n’t require to put them out before preparing them for what it ’ll really be like out there .
You want to harden them off first .
It sound kind of gangsta , toharden offseedlings , but that ’s exactly the attitude they ’ll want when they make the conversion from being indoor to outdoor plants .
What does it mean to harden off seedlings?
Hardening off your seedling is the full of life step of acclimating them to the outdoors to ascertain their survival . You do n’t require to transplant seedling now in the garden without “ weaning ” them first , and this operate for vegetables , herbs , and flowers .
Up until this point , your seedlings have been protected from wind , rainwater , cold , heat , and intense sunlight . They need to toughen up before you fling them into the abstruse death of the pool , so to talk .
Why ? For this simple reason : All plants have aprotective waxy cake on the leaves(called a epidermis ) that repels water , reduces the pace of dehydration , and filters harmful ultraviolet spark .
Seedlings that have been grown in operate circumstance indoors ( in a sunny window , under grow lights , or in a greenhouse ) have n’t fully make grow the epidermis and need time to build up their “ armour ” against environmental disturbances .
By step by step let out seedlings to the outside elements , you excite their lifelike defenses and give them time to adapt to their fresh surroundings .
What happens if you don’t harden off plants?
plant that were bulge out indoors are susceptible to transplant shock and heat stress if they ’re not hardened off the right way .
If seedling are leave out in direct sun all daylight , their leaves could get sear , curl under , or even fall off because they are n’t used to the intensity of unfiltered light .
Strong winds could dampen their base ( peculiarly if you ’re already deal withleggy seedling ) or snap them in half .
Wide swings in temperature because of hot daytime and nerveless nights could further accent soft seedlings , and even if they do supervise to live , they could become more vulnerable to pest and disease . Sudden inhuman temperature , in particular , can even stunt seedling ontogeny or stamp out them outright .
Do you need to harden off plants purchased from a nursery?
greenhouse - develop seedlings usually part in nursery before move outside . The commercial-grade cognitive process of propagating , transplanting , packaging , and sometimes shipping them intend they ’re already adjusted to the outdoors by the clock time you buy them .
While greenhouse plants that are displayed in full Lord’s Day do n’t need to be hardened off , smaller seedlings that exist under a shade structure are susceptible to shock if not harden off decent . You ’ll have the best opportunity at success if you inure off vegetable , herbs , and flowers before planting them in your garden .
In cosmopolitan , store - buy seedlings need less prison term to acclimate to the conditions in your yard . Set them out in dappled shade all Clarence Shepard Day Jr. the first 24-hour interval , then full Lord’s Day all sidereal day the 2nd day , and in the end overnight on the third day , making sure they have plenty of water every 24-hour interval .
How long do you have to harden off plants?
In general , the process of hardening off will take about one hebdomad , and sometimes up to two weeks if the weather has an unexpected and dramatic drop in temperatures .
If your region has hoar , you should time your seed starting in spring so the seedling can startle to go outdoors after the last frost date . ( purpose myplanting calendarto get a tradition sowing and transplanting schedule for your zip code . )
Wait until nighttime temperature are consistently in the humbled 50 ° Fs before you start indurate off leafy leafy vegetable and other nerveless - weather plants , or in the mellow 50 ° Fs for fond - atmospheric condition plants like tomatoes , peppers , and squeeze .
In some display case you may start to harden off seedlings earlier , but they ’ll need some form of frost protection at night , like frost covers , dusty frames , cloches , or unheated greenhouses .
How to harden off seedlings in 7 days
Day 0: Start hardening off seedlings when they’re a couple inches tall with their first set of true leaves.
That ’s correct : the process of indurate off seedling should startindoorsfirst .
Every day , as soon as your source evolve , sweep your hand back and forth across the seedling to simulate a picnic . This simple question strengthen their stalk and devise them for the solid gentle wind they ’ll face in the garden .
Day 1: Set your seedlings outside in dappled or partial sun for 2 to 3 hours.
Make certain the sphere is liberal of current of air and above 60 ° F . This could be under an eave , a covered porch , or a shady tree .
Give your seedling only 2 to 3 hours of Sunday in the afternoon ( the warm part of the day ) and be certain to check their moisture levels , as seedling have a leaning to dry out out quickly once they ’re out of doors .
Bring them back inside for the Nox . The next few twenty-four hours is what I care to call the “ saltation shuffle ” as your seedlings move in and out of the business firm .
Day 2: Set your seedlings outside in partial to full sun for 3 hours.
The next afternoon , put the seedling out of doors for 3 hours in partial to full sunshine . Somewhere with a light zephyr is also undecomposed for them at this detail .
Be sure to watch the weather for any dramatic change , and do n’t bury to make for them back inwardly .
Day 3: Set your seedlings outside in full sun for 4 hours.
Put them someplace warm with a soft breeze , if possible , and check that they do n’t sit dry and wilted for a prolonged period of clip .
Bring the seedlings inside for the night .
Day 4: Set your seedlings outside in full sun for 5 to 6 hours.
convey them outdoors earlier in the day so they experience some cool temperature , and give them 5 to 6 full hr of direct Dominicus .
Keep the potting soil moist , and bring the seedlings inside at the end of the Clarence Shepard Day Jr. .
Day 5: Set your seedlings outside in full sun all day.
Leave your seedlings outside all day in the sun and the breeze . They ’ll most likely require to be watered at least once if it ’s a very warm day , so be sure to keep an eye on them .
Also — speaking from personal experience — you ’ll want to check for garden visitors that might think your seedling are a complimentary buffet . Squirrels , razzing , and rabbits have a tendency to take a nibble if your seedlings are looking especially tasty .
Before it gets dingy , bring the seedlings back inside .
Day 6: Set your seedlings outside all day and all night.
Today will be their first sleepover in the garden ! Leave your seedlings outdoors in full sun and through the night as long as temperatures stay well above freezing .
It ’s significant to keep seedling off the earth , as mice , vole , and other pests have an appetite for warm new increase and will be quick to decimate your seedlings overnight .
Day 7: Graduation day!
Your seedling are hardened off and can be transpose to their permanent localization in the garden , whether it ’s in soil or a magnanimous container out of doors .
Your best probability at transplant achiever is on a cloudy day ( to give seedlings time to adjust to yet another new environs ) , though at this stage , they should be capable to take verbatim sun , spring rains , and easy hint .
If frost is look over the next calendar week or two , be certain to protect your plants with frost cover . Unfortunately with hail and strong , stale winds , your plant can suffer damage , no matter how carefully you ’ve hardened them off .
revelation : If you shop from my article or make a leverage through one of my links , I may get commission on some of the product I advocate .
How to harden off seedlings in less than 7 days with these garden shortcuts
Sometimes , you may castrate the amount of time it takes to indurate off seedlings . I do n’t recommend skipping this of import footmark , but if you ’re pressed for time or need to move those seedlings out of your kitchen stat , you’re able to judge one of these shortcuts .
Shortcut #1: Transplant your seedlings outside during a period of cloudy weather.
If the weather is on your side , with at least a week or two of mild , clouded days , you could implant your seedlings in the filth immediately .
This method is wild , particularly for climate that have dramatic shift between twenty-four hours and Nox ( like we do here in Central Oregon ) or higher elevations with blaze sun .
But if you endure in a meek climate and are confident of your local weather figure , you may save at least a week by transplanting your seedling as shortly as they have their first unfeigned leave-taking .
Shortcut #2: Use a portable “mini greenhouse” to protect your seedlings outside.
I ’m a adult lover of Wall - group O - Ethel Waters , which take care like water supply - fill up teepee that you aim around your plants . I ’ve seenred versionsandgreen edition , but they ’re pretty much the same product and you ’ll require one for each plant . ( you may see them in action here when Igrew tomatoes in containers . )
The Wall - group O - Water collect heat from the sunshine during the day ( while also protecting little seedling from wind ) and radiates the heating system back out at night , keeping them snug and warm .
By the time the seedling outgrows the Wall - o - urine , it ’s hardened off naturally — all without you doing the springtime shuffle .
This place updated from an article that originally appeared on March 24 , 2014 .
View the Web Story onhow to harden off your seedlings .
