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Sunburned Seedlings – Causes & How To Prevent It

Most gardeners have experienced having some seedlings get sunburnt. Luckily, a little bit of sunburning on seedlings is relatively treatable with a little extra TLC. Similarly, preventing sunburning on seedlings is also relatively easy once you know where and when is the best place and time to transplant your seedlings outside.

In this article, we will be explaining everything that a gardener will need to know about what to do with sunburnt seedlings. 

What Do Sunburnt Seedlings Look Like?

Minor sunburning on seedlings will give their leaves a washed out appearance. This is either a white or washed out green color on the parts of the leaves most exposed to the sun.

Additionally, blistering can also occur and show up in the form of brown spots. In very extreme cases of sunburning, the leaves on a sunburn will be completely brown and appear to be dead and very dry. In these extreme cases, the seedlings can die due to sunburning. 

How Do You Treat Sunburnt Seedlings?

There are several different things that you can do to treat some minor sunburning on seedlings. These things include using a shade cloth, continuing the plant’s water and fertilizing schedule, and keeping an eye on your plant’s growth. Here are some ways that you can treat sunburnt seedlings. 

Use A Shade Cloth

Shade cloths work to protect plants and seedlings by reducing the intensity of the sunlight hitting the seedlings. This will prevent them from receiving even more sun damage when they are planted outdoors. Of course, if your seedlings are still planted in containers, limiting the time they spend in the sun is also an option. 

Continue Fertilizing And Watering

You must continue the seedling’s fertilizing and watering schedule when they are sunburned minorly. This is because these things are crucial for seedlings’ proper growth and development. 

Keep An Eye On Your Plant’s Progress

Of course, you will still need to continue monitoring your seedlings. This way, you can quickly notice if the sunburning is getting worse or if there are any issues with your seedling’s development or growth. 

How Do You Save Burnt Seedlings? 

If your seedlings have received major sun damage, then there are some things that gardeners can do to save them. Doing things like pruning dead leaves, using a shade cloth, temporarily using a liquid fertilizer, and increasing watering can sometimes help to repair a sunburnt seedling. Here are some ways to save a severely sunburnt seedling. 

Use A Liquid Fertilizer

Using a liquid fertilizer can potentially help to revive a sunburnt and dehydrated seedling. This is because liquid fertilizers provide the sunburnt seedling with moisture and nutrients needed for repair, further development, and growth.

Prune Away Dead Leaves 

Dead leaves resulting from severe sunburning will not grow or develop further. As a result, these dead, brown, and dry leaves should be pruned away. Unfortunately, if all of the leaves on a seedling have died due to sunburning, the seedling is likely dead. 

Temporarily Increase Watering

In addition to liquid fertilizers, temporarily increasing your watering could help revive sunburnt seedlings. This is because sunburnt seedlings are often dehydrated as well. However, you should be very careful with doing this. 

Use A Shade Cloth And Monitor Your Seedling’s Process

Like with minor sunburning, using a shade cloth will prevent your seedlings from further sun damage. Additionally, you will also need to closely monitor your seedling’s progress as there is a chance that they will not grow if the sun damage is extensive. 

How Do I Protect My Plants From Sunburn? 

There are some things that gardeners can do to prevent sunburn in plants and seedlings. Gradually exposing your seedlings to sunlight, using a shade cloth, and transplanting your seedlings on an overcast day can help prevent sunburning in seedlings. Additionally, doing your research on how much sunlight each of the plants in your garden needs can help prevent sunburning. Here is how you can protect your plants and seedlings from sunburning. 

Gradually Expose Your Seedlings To Sunlight 

Seedlings need to be acclimated to full sunlight slowly. This is because seedlings are usually very delicate, and they could easily become sunburnt if they are exposed to large amounts of sunlight too soon.

As a result, many gardeners will slowly acclimate their seedlings to sunlight by bringing them outside for only small amounts of time in the beginning. This amount of time is usually for only one to two hours in the beginning and then slowly making this time length longer. 

Use A Shade Cloth

If you believe that you have planted your seedlings outside too soon, placing a shade cloth over them will provide the protection needed to prevent sunburning. 

Transplant Your Seedlings On An Overcast Day 

Overcast days will not bombard your seedlings with full sunlight. As a result, planting your seedlings outdoors will allow them to acclimate to the sunlight more easily. 

Do Your Research On How Much Sunlight Each Of Your Plants Need

Some plants need a lot more sunlight than others. As a result, you must research how much sunlight each plant in your garden needs to prevent sunburning. 

Will Seedlings Recover From Sunburn?

Many seedlings will recover from some minor sunburning. However, severe sunburning characterized by brown and charred leaves will kill a seedling

Things To Consider

There are some additional things that gardeners should consider about sunburning in seedlings. Knowing when the best time is to transplant seedlings outdoors and where you should prevent them to prevent sunburning can greatly benefit the results in your garden. Here are some other things to consider about preventing sunburning in seedlings. 

When Is The Best Time To Transplant Seedlings Outside? 

The best time to transplant your seedlings outside is at a time when the temperature will be warm enough for them to survive. This can differ depending on the plant type. In addition to this, many gardeners like to transplant their seedlings outside on an overcast day to acclimate their seedlings to sunlight. 

Where Should You Plant Seedlings To Prevent Sunburn

Planting your seedlings in a partially shaded part of your garden can help to prevent sunburn. For seedlings that will later need full sun, using a shade cloth will likely be a better option.