- Hardening Off Your Seedlings
- What is “Hardening Off” Your Plants and What Does it Mean?
- Hardening Off Vegetable Seedlings
- Why You Need To Harden Off Vegetable Plants & Flowers
- Why Should You Harden Off Seedlings?
- Steps to Harden Off Your Transplants:
- Transplanting Hardened Off Seedlings to the Garden
- Hardening off is an important step to reduce stress on your plants. If you harden off seedlings properly, they’ll be strong and able to withstand full sun, light breezes, spring rains, and fluctuating temperatures. Once transplanted to the garden, the plant’s energy will be focused on establishing roots and growing rather than surviving.
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- How to harden off seedlings:
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- Steps for Hardening off Seedlings
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- Hardening Off Plants
Hardening Off Your Seedlings
Moving is one of life’s most stressful events. Imagine how trying it would to move from a perfect climate where it’s always 70 degrees, calm and sunny, to a harsh and windy climate where it gets really cold at night and the sun is burning hot during the day.
Put yourself in your seedlings shoes. If you had to move from San Diego to Montana, wouldn’t you want some time to adjust?
You’ve started your seeds. Kept them hydrated just right. Transplanted them. Maybe fed them a diluted dish of fertilizer or two. They are tall now.
Your seedlings may look like they are ready to go it on their own in your garden, but be kind, prepare them for the extremes of your garden with a process called ‘hardening off.’
The author of ‘Grocery Gardening’, Jean Ann Van Krevelen, said you shouldn’t skip the step of hardening-off your seedlings. Young plants may not make it if planted directly into your garden with out a transition.
“When seedlings are grown inside in a controlled climate, they don’t have the opportunity to develop the strength and structure to live out in the elements. They need to get acclimated to their new home, “ said Van Krevelen.
To harden off your seedlings, gradually introduce them to the outdoors. It helps to store your seedlings in trays, at this point, to make transporting the plants easier.
“Take your seedlings to a protected location outside for one hour for the first day,” she said, “Do this each day for a week. Add one hour for each day of the process. By the end of the week, you’ll be at 7 hours and the plants will be ready to be transplanted,”
While inside, seedling stems haven’t been exposed to winds. Plants, like us, need to start our workouts and gradually increase the intensity to become strong. So early on in the hardening off process, provide seedlings shelter.
“Don’t put them in direct sun. Don’t put them in a windy location. Keep in mind, they are just babies,“ said Van Krevelen.
If you want to help your plants beef-up early, you can add a fan to the area where you are storing your seedlings. Use the fan to gently move the air. Too much direct breeze from a fan could dry out the seedlings and do the same damage wind would in the garden.
Gardeners have different approaches to the watering aspect of the hardening off process. Van Krevelen keeps her seedlings evenly moist from grow light to garden.
“Provide consistent moisture. Seedlings are susceptible to any extreme until they are established,” she said.
Horticulturalist Erica Shaffer agrees. “Don’t send your babies into the big, bad world of your garden thirsty and hungry,” she said.
Good gardeners aren’t perfect. And the process of hardening off doesn’t have to be executed perfectly or uniformly to be highly successful. If you forget to take your plants out one morning before work, just start back up the next day. If the spot you chose for them becomes too sunny as the day went on, all is not lost. Plants are a forgiving lot and will hang in with you as long as you give them a little attention.
There is a bit of hassle involved in schlepping the plants outdoors and back in again each day over a week. But after gently caring for your baby plants for weeks, the added effort is good insurance that your plants will leave your nest safely and do well in your garden. After all, don’t you want to shield every thing you love from unnecessary stress?
Find out how to move your indoor-sown young plants to the garden outdoors—without stalling their growth!
How to Successfully Harden Off Indoor-Sown Plants
‘Hardening off’ is the process of gradually acclimatizing indoor-sown plants to outdoor conditions.
For most plants, begin hardening off a week before the final frost date for your area. Our Garden Planner uses data from your closest weather station to recommend when it’s safe to plant out, providing a helpful guide to work back from.
Choose a sheltered spot to harden off your plants. An unheated greenhouse or cold frame is a great tool for this, or you can cluster pots into buckets, crates or boxes to keep the wind off. Don’t place pots directly on the ground where they can easily be knocked over by birds or attacked by slugs.
Begin hardening off on a still, cloudy day when temperatures are fairly steady. Water plants before they go outside. Place them into your sheltered spot for just two hours on the first day. The next day, leave them out for two more hours, with perhaps an hour’s direct sunshine in the morning. Gradually increase the length of outdoor time and direct sunshine over one to two weeks. You can then leave them out overnight if there’s no danger of frost.
In cold winter regions, plants – particularly tender plants such as tomatoes and peppers – will need to be prepared for the cooler nights early in the growing season. Towards the end of the hardening off period, cover your crops with fleece or row covers to protect them overnight. Once crops have been planted into their final positions, be alert for unexpected cold snaps and cover tender crops if necessary.
It’s a good idea to grow a few more plants than you need so you can hold some back just in case. Bought-in plants may also need hardening off, particularly if they have been kept in sheltered conditions.
Read our full page about transplanting seedlings.
Also: Be sure to check out the Almanac Garden Planner! We’re offering a free 7-day trial to create your best garden.
What is “Hardening Off” Your Plants and What Does it Mean?
If this were any other year, we’d still be enjoying Spring’s annual show of Daffodils, Hyacinths, Tulips and Bluebells. Instead, Mother Nature has fooled us into thinking it’s late April and time to go plant shopping. Nurseries are scrambling to fill our overwhelming desire and insatiable need for annuals, perennials, herbs and vegetables.
The weather is so conducive and our urge to plant is so overwhelmingly strong, we’re willing to shop until we drop and plant until our knees and backs cry “UNCLE!” Release that shovel, grab a cold drink and relax.
Let me teach you about “hardening off” your springtime annuals and perennials and why it’s one of the most important steps to giving your plants the right start this spring.
So, what exactly does “hardening off” your plants mean? If you have ever spent all morning picking out your favorite plants at the local nursery, planted them lovingly, only to have them wither and look pitiful for a few weeks, your plants weren’t hardened off.
Did you wonder why those huge, robust and tropical Elephant ears that were so stunning in the garden center became shredded on that windy day? Have you ever have some Hosta that looked like they were sunburned, even though you only left them in the sun for a day or two?
Hardening off is all about acclimating your plants to their new home. They need to be slowly introduced to their new digs.
Generally, the plant material you buy from your favorite greenhouse has spent all winter and early spring under very controlled conditions. The greenhouse temperatures are normally consistent. Water and fertilizer are given at regular intervals and the plants have been “babied” their entire lives. Gentle greenhouse fans barely rustle the plants’ leaves.
In your garden, spring breezes that make for superb kite flying can shred plants recently planted in the ground. Because they haven’t been exposed to sun, wind and rain, the cuticle of the plant is soft and tender, allowing any change at all to throw the plant into a tizzy. They need to be hardened off- you can do it successfully a few ways.
The first way to harden off is by withholding water. You can stress the plant enough that it actually responds by “toughening up.” By waiting to water until the plant exhibits a wilted appearance, you build a stronger plant. Doing this for a week to ten days will toughen up the plant enough to place it in the ground. I think of my plants as my “little babies” and I just don’t have the heart to do this. I prefer hardening off my plants another way.
I place my plants under a covered patio if I know that they have been grown in a greenhouse. I leave them under the protective cover of the patio roof for 3 or 4 days and water normally. Then, I’ll move the plants outside, on a sunny day, for a few hours each morning. I bring them back in about 11 o’clock. I’ll do this for 3 or 4 days, lengthening the time I leave them outside each day. Then, around the 9th or 10th day, I leave them outdoors permanently.
I find this method less stressful than watching my plants wither.
Of course, if temperatures get below 45 or 50 degrees, I’ll cover them with a frost blanket or sheet for the night. Make sure to pull the covering off in the morning. Additionally, when you bring your houseplants outdoors this spring, treat them the same was as you do your new greenhouse plants. I’ve seen many cases of eager gardeners placing their houseplants outside on a beautiful day, only to see them sunburned and withered at the end of just one day. The heartbreak IS preventable.
A third way to harden off your plants is to place them in a cold frame. I got one for Christmas this year and have really enjoyed starting plants from seed in it. Unfortunately, my cold frame isn’t large enough to accommodate the plants I am hardening off. I find the method of “babying” them easy and stress free.
Plants that have been exposed to the elements for a week or more in the nursery don’t need to be hardened off. Just be sure that, once they’re planted, you remember to cover them if we happen to get low temperatures at night. This has been a wacky spring, Mother Nature just might have a frosty night up her sleeve!
By treating your plants right in the beginning, they will return the favor and reward you with vigor and stupendous growth all season long. So, get out there and shop- just make sure that you harden them off becomes a regular part of your planting process!
Hardening Off Vegetable Seedlings
Back to Seedling Care
Hardening is the process of exposing transplants (seedlings) gradually to outdoor conditions. It enables your transplants to withstand the changes in environmental conditions they will face when planted outside in the garden. It encourages a change from soft, succulent growth to a firmer, harder growth.
- Begin hardening transplants 1-2 weeks prior to setting out plants in your garden.
- The easiest way to harden transplants is to place them outside in a shaded, protected spot on warm days, bringing them in at night. Each day, increase the amount of sunlight the transplants receive.
- Don’t put tender seedlings outdoors on windy days or when temperatures are below 45° F. Even cold-hardy plants will be hurt if exposed to freezing temperatures before they are hardened.
- Reduce the frequency of watering to slow plant growth, but don’t allow plants to wilt.
- A cold frame provides an excellent environment for hardening off transplants.
- After proper hardening, tomato plants can usually tolerate light and unexpected frosts with minimum damage.
- The hardening process is intended to slow plant growth. If carried to the extreme of actually stopping plant growth, significant damage can be done to certain crops. For example, cauliflower will produce thumb-sized heads and fail to develop further. Cucumbers and melons will stop growing if hardened too severely. They may be left outside overnight if the temperature will not fall below 50° F.
Please e-mail us when you have questions or problems – http://extension.umd.edu/learn/ask-gardening
So just exactly what does it mean to harden off vegetable plants and flower seedlings before planting outdoors?
And, why is it so important?
Those two questions are often asked by gardeners every spring. And with good reason.
A young tomato plant grows indoors, awaiting life in the garden.
Whether raising plants from seed at home, or purchasing transplants from a nursery or greenhouse, the process of hardening off is a big key to a plants short and long term health and success.
Why You Need To Harden Off Vegetable Plants & Flowers
In a nutshell, hardening off is the process of toughening up young, tender plants for life outdoors vs. Mother Nature.
Whether raised in nurseries or at home, tender seedlings are simply unprepared for life outdoors.
Inside in a controlled environment, there is no such thing as a strong wind or heavy rain to whip and damage tender foliage.
Both flowers and vegetables need time to adjust from their cozy life indoors before being planted outside.
Nor are there any worries of intense sunlight or blazing daytime temperatures to quickly dry out plants. Or even a cold night that might bring a damaging or deadly frost.
But hardening off plants allows tender transplants time to slowly adjust and prepare for all of those harsh outdoor conditions.
And in the process, keep them safe from injury, transplant shock, or even complete failure.
The Process – How To Harden Off Vegetable Plants And Flower Seedlings
For those who grow their own seedlings indoors at home, the hardening-off process should begin about three weeks before planting day.
Begin by setting plants outside on warm days (around 55 degrees or above) in a protected area.
We use 1 x 12″ boards screwed together and placed on the ground around our flats. It keeps the wind from knocking them over, but still allows them plenty of sunlight and air.
While hardening off, we use 1 x 12″ wooden boards placed around our plants to protect them from harsh winds.
Porches and patios are also ideal for this task.
It gives plants their first taste of outdoor living, while still having a bit of protection from full sun or heavy winds.
For the first week or so, bring plants inside at night to keep them safe from cool or freezing temperatures.
As spring continues to warm the air, allow transplants more and more time outdoors. In fact, as long as night time temps stay above 45 degrees, keep them out around the clock.
Seedlings indoors have it easy. But outdoors, a whole new world awaits!
As planting day approaches, plants should be spending nearly all of their time outdoors. Only bring indoors if a frost, high winds, or a heavy storm is in the forecast.
By following this process, your plants will be more than ready to handle the shock of transplanting.
What About Nursery & Greenhouse Plants?
Store purchased plants are usually a bit larger and more robust than those grown at home.
But even so, most have still spent all of their life protected indoors.
After hardening off, plants are ready for Mother Nature.
And a bit of hardening off for a few days or a week can go a long way towards helping them to adjust to outdoor life.
Start by sitting out newly purchased plants outside in a semi-protected area
Keep them from strong winds and heavy rains, but allow them to stay outside around the clock unless a frost or storm is in the forecast.
These plants are usually much larger, so a week or so is usually more than enough time to harden them off.
Now it’s all about getting those plants off and running! (See : The Ultimate Planting Day Guide – How To Start Your Plants Off Right In The Garden!)
A Few Exceptions To The Rule
There are a few exceptions where you do not need to harden off vegetable plants and flowers.
If you are purchasing late in late spring, or from nurseries who have already placed their plants outdoors – simply buy and plant!
Happy Spring and Happy Gardening! Jim and Mary
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How & Why To Harden Off Vegetable Plants & Flowers Before Planting Tagged on: hardening off flowers hardening off plants hardening off vegetable plants how to harden off plants transplanting vegetable seedlings
If you grow your own vegetable seedlings indoors under lights, or if you purchase transplants from a nursery greenhouse, you will need to adapt your seedlings before transplanting them into the garden. This adjustment process is called “Hardening Off.”
Hardening off is the process of adapting plants to the outside, so they can get used to sunlight, wind, rain, cool nights, and less frequent watering and fertilizing. The hardening off period allows your seedling to transition from the comfortable growing conditions under lights or in a warm greenhouse to the normal conditions they will experience in the garden.
I like to allow at least a week to harden off seedlings before transplanting to the garden. Depending on the weather, sometimes two weeks are necessary. Be patient and you will be rewarded with healthy and strong plants.
Why Should You Harden Off Seedlings?
Sunlight is stronger than grow lights and can burn foliage if the seedlings are placed in the direct sun. Light breezes can sap your plants’ moisture and cause weak stems to break. Cooler nighttime temperatures may stunt the plant’s growth or even kill a seedling that is not used to it. Gradual exposure to the outside elements allows the plants to toughen up and become accustomed to being outside.
Steps to Harden Off Your Transplants:
1. Begin Hardening Off Your Plants in a Sheltered Location: About a week or two before your transplant date, place your plants outdoors in a protected spot for a few hours on the first day. I like to situate my seedlings on a patio table under an umbrella to shade them from the sun and shelter from rain. The table is located in an area that is also protected from harsh wind. Allow your plants to remain outside for a few hours, then bring your plants back inside.
Keep an eye on the weather during the hardening off period. Temperatures can drop to unseasonable levels quickly, and high winds can destroy tender foliage and knock over seedling trays. Watch the weather for early-season frost or unsettled conditions and bring transplants indoors until the weather returns to normal.
2. Increase Outdoor Exposure a Little Each Day: Increase the amount of time that the seedlings spend outside gradually to allow the plants to adjust slowly. Continue to harden off seedlings by moving the plants outside while temperatures are warm and then back inside at night when the temperature is cool. I usually add a couple of hours each day as long as the weather cooperates. Alter the shade or move the seedlings to a location that receives morning or evening sun, so they are exposed to a little more sun each day. Allow the seedlings to experience gentle breezes. Even filtered sunlight and light breezes can deplete your plants’ moisture, so check on them frequently and give them enough water, so they do not wilt.
3. Leave Seedlings Outside Overnight: Eventually, allow your plants to stay in full sun and outside as long as night temperatures do not drop below freezing. If it is going to get below freezing move the plants indoors. Resume the hardening off process once temperatures return to normal conditions.
Cool season crops such as broccoli, Brussels sprouts, cabbage, celery, lettuce, onions, parsley, peas, spinach, Swiss chard, and other hardy greens can tolerate low nighttime temperatures of around 45°F once they have had time to adjust. Light frost won’t harm these seedlings after these are hardened off.
Warm-season crops such as tomatoes, peppers, eggplants, melons, cucumbers, and some herbs prefer warm nights, at least 60°F. They can’t stand below-freezing temperatures, even after the seedlings are hardened off. So continue to bring indoors if nights remain cool.
Transplanting Hardened Off Seedlings to the Garden
After your seedlings are hardened off, they are ready to be transplanted into their permanent location in the garden.
Prepare your garden bed ahead of time. If the weather has been dry, water the bed thoroughly the day before you plant.
Choose a cloudy day with no wind and transplant in the late afternoon or evening to give your plants time to adjust without the additional challenge of the sun.
Water the seedlings well after planting.
You May Also Like:
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- How to Build a Grow Light Shelf
- Using Soil Blocks to Grow Seedlings
- Planning Your Vegetable Garden: Mapping the Garden Beds
How to harden off seedlings
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The first year I started my own seeds indoors, I planted around ten flats of annual flowers and vegetables, growing them on top of my mother’s dining room table (sorry mom!). I was sixteen years old and a fairly novice gardener. When the April showers finally cleared and the bright spring sun came out, I had the brilliant idea of taking those plants – whose only light source had been a modest west-facing window – and moving them outdoors to give them a dose of early May sunshine. Oops! Within an hour, every single plant was fried and I had no idea what I had done wrong. I obviously needed a lesson in how to harden off seedlings.
Hardening off is a simple, but necessary step for seed starters. Growing your own plants from seed offers many rewards – save money, grow varieties not available at local garden centres, and enjoy a steady supply of top quality seedlings for succession planting. But, as I learned that fateful spring, you need to properly harden off your seedlings before introducing them to the ‘real world’ outside.
These orach and amaranth seedlings are ready to be moved to their raised bed.
Why? Simple! All plants have a waxy leaf cuticle that protects the foliage from sun and wind, and seedlings that have been grown indoors – in a sunny window, under grow-lights or under glass in a greenhouse – have not fully developed their cuticle layer and need a bit of time to build up this horticultural suit of armor. Hence, the hardening off process.
How to harden off seedlings:
Hardening off is not difficult and will take about a week in total.
Step 1 – Place the young plants outdoors in a shady spot.
Step 2 – Bring them back indoors again that night (I call this ‘the spring shuffle’).
Step 3 – Continue giving them daily shade for 3 to 4 days, bringing them indoors at night if the temperature becomes unseasonably cold or frost threatens.
Step 4 – By day 4, begin introducing increasing amounts of sunshine each day, so that by the time a week has passed, the plants have become adjusted to full sunshine.
Do you do the spring shuffle?
How To Harden Off Your Seedlings
These days, a great many gardeners are growing the plants for their garden from seeds. This allows a gardener to have access to wide variety of plants that are not available in their local nursery or plant store. Growing plants from seeds is easy, as long as you take a few precautions. One of those precautions is to make sure that you harden off your plants before setting them out in your yard and garden.
Why You Should Harden Seedlings
When plants are grown from seed indoors, they frequently are grown in a controlled environment. The temperature is pretty much maintained, the light is not as strong as full sunlight outside and there will not be much environmental disturbance like wind and rain.
Because a plant that has been grown indoors has never been exposed to the harsher outdoor environment, they do not have any defenses built up to help them deal with them. It is much like a person who has spent all winter indoors. This person will burn very easy in summer sunlight if he/she
has not built up a resistance to the sun.
The way to help your seedlings build up a resistance is to harden off your seedlings. Hardening off is an easy process and will make your plants grow better and stronger when you do plant them out into the garden.
Steps for Hardening off Seedlings
Hardening off is really just gradually introducing your baby plants to the great outdoors. Once your seedlings are big enough to plant out and the temperatures are appropriate for planting outside, pack your seedling in an open top box. The box is not absolutely necessary, but you will be moving the plants around quite a bit in the next several days, and the box will make transporting the plants easier.
Place the box (with your plants inside) outside in a sheltered, preferably shaded, area. Leave the box there for a few hours and then bring the box back indoors before the evening. Repeat this process over the next few days, leaving the box in its sheltered, shaded spot for a little longer each day.
Once the box is staying outside for the entire day, start the process of moving the box to a sunny area. Repeat the same process. For a few hours each day, move the box from the shaded area to the sunny area increasing the length of time each day until the box is in the sun all day.
During this process, it is best to bring the box in every night. Once the plants are spending the whole day outside, then you will be able to leave them out at night. At this time, it will also be safe for you to plant the seedlings out in your garden.
This whole process should take just a little longer than one week. Taking this one week to help your plants get use to the outdoors will help ensure that your plants will have a much easier time growing outside.
Need help with what to do in your garden?
Plants that have been kept indoors or in a greenhouse can’t be planted outside straightaway in spring – you need to acclimatise them first. This process is known as hardening off. If this doesn’t happen, exposure to cold winds or a sudden drop in temperature can seriously weaken or even kill the plants.
You’ll need to harden off young plants that have been raised on the windowsill or in the greenhouse, small veg or ornamental ‘plug’ plants ordered by mail order and tender plants that you’ve kept in the greenhouse over winter.
Caption: Hardening off will help prepare tender plants for life outdoors
How to harden off
Using a coldframe, makes hardening off a much easier task. Position your frame so it faces south or south-west to receive maximum sunlight. Ideally it will be protected by a wall or fence. Don’t stand it on low ground where cold air collects. Before using, wash down the glass and frame with a garden disinfectant. When Which? Gardening magazine trialled different methods of hardening off plants, the method that worked best was:
- Keep the coldframe lid half open during the day when sunny for the first six days and closed at night.
- Then keep the coldframe lid fully open during the day when sunny for the next six days and closed at night.
- Finally keep the coldframe lid fully open both day and night for the last six days.
When to harden off
Depending on the plant, you should be hardening off around the time of the last frost dates in spring. Seek local advice and check weather forecasts.
What to harden off, and when
When they’re large enough to handle, hardy pansies, cabbages and Brussels sprouts can be moved to the coldframe.
Alyssum and antirrhinum can cope with a few light frosts, so can be moved to the coldframe 4-5 weeks before the last frost date.
Lobelia, Phlox drummondii and mesembryanthemum should be hardened off before the last frost dates.
Other tender bedding (e.g. begonia, petunia, impatiens, salvia and pelargonium) and tender vegetables (e.g. courgettes cucumbers, sweetcorn, runner beans and tomatoes) should be hardened off around the last frost.
Coldframes offer great scope for DIY and improvisation – half of all Which? Gardening members who own a coldframe made their own.
Their advice is to:
- Make sure it’s big enough and tall enough for the plants you want to grow.
- Make sure the coldframe is easy to open, close and ventilate.
- Solid sides are generally preferable as these offer more insulation and reduce the Which? works for you risk of scorching on sunny spring days. Bricks, breeze blocks, old railway sleepers or other second-hand timbers are all suitable. If you can arrange it so the sides aren’t permanently fixed, you can dismantle the frame when you don’t need it any more. If you site your coldframe in a permanently shady position, or use it to raise summer crops such as melons, then it would be better to have transparent sides.
- The top needs to be transparent, easy to lift and remove, and capable of being propped in a semi-open position for ventilation. Glass is excellent for transparency and its weight reduces the risk of it blowing away. Second-hand windows are good for this. Plastic has the great benefit of being unbreakable – twinwalled polycarbonate is often used for packaging and may be available as off-cuts.
Coping without a coldframe
On a frosty morning, look round your garden and take a note of the places where there is little or no frost, for example, a sheltered, south-facing wall or fence, under a hedge or on the sheltered side of the house. These should prove ideal places for hardening off plants later in the spring.
Stand your plants in a sheltered spot outdoors during the day. To begin with, leave them for only a few hours when it’s mild and gradually increase the time until, after two or three weeks, they can be left out all night. However, be ready to cover them with newspaper or a double layer of horticultural fleece if frost is forecast.
What to do if you’re caught out by frosts
Even experienced gardeners can be caught out by an unusually late frost. If you find recently hardened-off plants have been frosted, try to make sure they thaw out as slowly as possible.
If possible, move the plants into permanent shade until they thaw. Otherwise, you could try draping newspapers or netting over them.
Hardening Off Plants
We harden off plants because those that are started indoors are not yet ready to be exposed to wind or sun. Much like humans, plants need to slowly increase the amount of sunshine they’re exposed to or they’ll get burned!
If you don’t harden your plants, the tender plants will get burned by the sun, the shock of cold, or the wind. Some plants may recover from burn (even fully), but their growth will be set back a few weeks while they recover.
How to Harden Plants
The best way to harden plants is to put them outside for a few hours the first day and then bring them in at night. Each day, increase the number of hours they are exposed to sunshine until finally after 3 or 4 days you can leave them out all night.
Partly cloudy days are perfect for hardening plants. If it’s a strong sunny day, set them in the shade, or ideally in part shade, for the first day. Using Reemay cloth, or floating row cover, to shade the plants is a good approach to hardening them on a sunny day.
For a little extra protection
Try this trick! Cut out the bottom of a gallon milk jug and place over your new transplant, burying the bottom of the jug in to the soil an inch or so deep. Remember to remove the jugs when you water the plants, or water each one through the hole on top of the jug.
Gardening Tips Gardening bedding plants freeze frost frost protection garden hardening off season extension transplanting