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How To Harden Off Plants – Why Hardening Off Is A Must For Young Transplants!

This week’s podcast and corresponding article are about how to harden off your vegetable and flower plants, and why it is so important to do so for gardening success!

So what exactly does it mean to harden off vegetable plants? Whether you grow vegetable and flower plants from seed, or purchase flats from a nursery, it is vital to prepare them for life outdoors. This process of getting plants “ready” is called hardening off.

You can listen in below to our complete podcast on how and and why to harden off your plants, or read on for the full-length article. Be sure to check the resource links at the end of the article as well. They are chock full of great additional reads and links!

Why To Harden Off Vegetable Plants

For many gardeners, hardening off vegetable and flower transplants is one of the most confusing topics of all. And yet, it can be the difference between sweet success, and total failure.

Getting your plants ready for life outdoors is vital to both their short and long term success. In many cases, if unprepared for what nature can bring, it can stunt a plant’s future growth. But more than that, sometimes it can cause total plant failure!

Up until the time vegetable transplants go in the ground, they have had an easy life. Whether growing in a nursery, a home & garden store, or indoors in your house, they have had shelter from the perils of the great outdoors.

harden off tomato plants
This tomato plant went right from the indoors to the outdoors – and it is struggling to handle its new surroundings! If plants are not given a chance to slowly adjust to the outdoors, trouble can loom.

Inside, there are no wind gusts that pop up to snap their fragile stems. Nor are there hard rains that can pelt a tender young seedling into the ground. Just the gentle still air and frequent easy waterings from their caretaker.

But the easy protected life for young seedlings doesn’t end there. There are also no worries of cold mornings and evenings to chill them, or hot afternoons to scald their foliage and dry them out.

The Comforts Of Indoor Life – How To Harden Off Plants

Indoors, there is the constant warm temperature of an indoor environment, coupled with the perfect amount of lighting. And with great soil, they have had the perfect amount of food as well.

When you compare it to raising a youngster, it really comes down to seedlings in their first few weeks of life being much like an incredibly spoiled child! That is, as long as you, or the folks working at the store have been diligent about keeping their water supplied on a regular basis.

But all of this perfection and coddling changes in an instant once they are planted outdoors. And it is exactly why they need to be prepared long before that big day comes, or else they will struggle to survive.

how to harden off transplants
These peppers will need to spend a bit of time outdoors before going in to the ground. This will help them adjust to outside life as well as prepare them for the storms and wind mother nature can bring.

How To Harden Off Vegetable Plants

Plants need time to adjust to the sunlight, wind, and temperature swings of the great outdoors. But just how much time they will need to spend adjusting depends on several important factors.

First and foremost, it matters whether you have raised your own seedlings, or purchased them at a greenhouse. Another factor will be just how large your transplants are, and where they will be going in the landscape.

With those thoughts in mind, let’s start by taking a look at the best methods to harden off flower and vegetable transplants, starting with seedlings you have raised at home. After that, we will cover how to help plants you might be purchasing at a nursery or greenhouse adjust for the outdoors as well.

Home Raised Transplants – How To Harden Off Vegetable & Flower Plants

The process of hardening off home-grown transplants should start 2 to 3 weeks before your outdoor planting day. This will allow appropriate time for tender transplants to toughen up and be ready for outside life.

tomato transplants
As each day passes, allow your plants to stay outdoors longer and longer. With a week to ten days to go, allow your plants to stay outside around the clock, only bringing them in if a cold snap is in the forecast.

Home raised vegetable and flower transplants are usually the most coddled of all. They are normally not quite as far along as store-bought versions. Some of this comes from raising the plants in natural light. (See: How To Start Seedlings Indoors With Success!)

Plants raised at home can be a bit more spindly or leggy, unlike transplants grown in big greenhouses with controlled lighting. Nurseries also tend to start their plants earlier and use a bit more fertilizer to power early growth.

Allowing Time For Home Grown Plants To Adjust

The good news is that a little more natural outdoor “adjusting” time for home-raised plants can go a long way toward creating bigger and healthier plants before planting day. And that of course, means better plants all summer long.

Begin by setting plants out during warmer afternoons in a protected area. Porches are perfect for this, as are areas near the house that offer protection. On these first few days, you want very little stress to your plants, so protect them from strong sunlight, wind and rain.

planting - how to harden off
After your plants have spent a few days outdoors around the clock, they are ready for planting!

Continue to let transplants get more time outside each day. With a week or so to go before planting day, only move them indoors when bad weather is in the forecast. Once they begin to adjust to life outdoors around the clock for a few days, they are ready for planting!

Store Bought Transplants – How To Harden Off Plants

So what about vegetable and flower plants you purchase in a store? For store bought plants, the hardening off process is a bit less involved, but still important for sure.

These plants are usually are further along in their growing process, so they will not require as much adjusting. Some have even been outside a bit on racks, but usually with added protection from covers when needed.

Allow store bought plants a few days to adjust when your bring them home. Set them outside on a porch or protected area to let them get accustomed to outdoor life. After that, as long as the soil is warm enough, they can go in the ground.

One final note on purchasing from a store -if you are purchasing plants at the very last stage of spring, when stores move plants outdoors to unload their stock – you can take them home and plant! Once warm temperatures are here to stay, there is no need to provide that extra support.

Podcast Resource Links – How To Harden Off Plants

Simple Garden Life is a website dedicated to keeping gardening fun, simple and enjoyable! We publish two new articles each week along with a new garden podcast episode every two weeks. This article may contain affiliate links.