What Is The Temperature For Growing Lettuce From Seed In The Greenhouse

If you’re not sure what the temperature is for growing lettuce from seed in the greenhouse, monitor your thermometer and aim for 70 to 75°F. A dilemma that a gardener might encounter with indoor cultivation of greens is what temp growing lettuce from seed in greenhouse works best. However, you don’t need to be intimidated by this crop because you already have a head start planting it in a greenhouse. 

The hardiness zone will help you know if lettuce will grow well in your state. In particular, lettuce crops will thrive best in zones 4 to 9, so keep this in mind before considering their cultivation. However, the greenhouse provides control over the indoor conditions, so with proper planning and maintenance, you can have fresh and healthy greens at your garden easily. 

What Is The Temperature For Growing Lettuce From Seed In The Greenhouse

What Is The Temperature For Growing Lettuce From Seed In The Greenhouse: Pointers To Consider

What determined the optimal temperature for growing lettuce from seed are seed germination and greenhouse condition. Additionally, always consider your growing zone or hardiness zone so you can make the necessary adjustments customized to your location. Each state has different climates and temperatures, so you may have to perform other greenhouse practices to maintain optimal conditions. 


Seed germination

When growing lettuce from seeds, it’s crucial to remember that its germination is significantly affected by the temperatures. You want to maintain the greenhouse at 70 to 75°F for optimal germination, although the seeds can germinate even at 35°F. Still, freezing conditions can injure the lettuce crops, especially when they have not yet hardened. 


Greenhouse condition

While lettuce is very adaptable in cold growing conditions, it’s still essential to maintain the greenhouse at 60 to 65°F for their growth. The crops will flower and seed at 70 to 80°F, and lettuce can withstand 80 to 85°F for a few days if necessary. But because you are growing from seeds, the temperatures are more influential in encouraging growth. 

For maintenance, the daytime temperatures that will work best for lettuce is 60 to 65°F and 50 to 55°F at night. It would also be helpful to choose a lettuce variety that is appropriate for your expected conditions. For example, if your location has a warmer climate, what’s suitable for you are heat-tolerant varieties. 

For greenhouses, extensions in universities recommend Leaf and Bibb lettuce varieties. For the former, Ruby Red, Grand Rapids, and Waldmann’s Dark Green are popular, while Mirlo, Roxy, Rosaline, and Cegolaine are common Bibb varieties in the greenhouse.


When To Grow Lettuce In A Greenhouse?

Since you’re starting from seeds, begin sowing as soon as the ground is workable or above 40°F. The soil temperature at 55 to 65°F will encourage germination as early as seven days. You can even have an earlier crop using a greenhouse by sowing before your last spring frost date. 

In some states like North Carolina, it’s possible to sow both in spring and fall. However, the Department of Horticultural Science of NC State Extension mentioned that spring lettuce also tends to fail, so it’s best to use transplants for this period. On the other, direct seeding is best for fall crop lettuce, but since it can get hot and dry, always check your temperature and irrigation in the greenhouse.

In eastern North Carolina, direct seeding is typical in late January and early February, while those in the west start in late March and early April.  If you’re doing a fall crop, sow 80 days before the first hard freeze. Depending on your area, you might even be able to plant a second crop in early winter. 


Other Lettuce Growing Requirements


Soil, feeding, and watering

Lettuce will grow best in a fertile, loose, and loamy soil with good drainage and pH of 6.0 to 7.0. You can sow the seeds half an inch deep before covering with another inch of soil. As for feeding, New Mexico State University mentioned using a balanced fertilizer before planting and weekly nitrogen feedings. 

What about the watering requirements of lettuce? In the greenhouse, it’s best to use a misting system to avoid overwatering the crops. A good measure is an inch of water every week so that you’ll get tender leaves.



Allocate four to six inches of space between rows and thin the plants with an inch or two between them. If you’re growing lettuce seeds indoors for transplants, later on, a good ratio is 6 ounce of seed per 300 square feet of the bed. This ratio will give you enough operations for an acre. 

Lettuce also works excellently in companion planting in the greenhouse. Chives or garlic can help deter aphids, so consider having rows of these crops in between your lettuce. You can also use blocks and containers for growing lettuce in the greenhouse, but pay attention to their root growth direction.  



Lettuce is a healthy and delicious staple for our meals, and cultivating them indoors is even accessible both for commercial and personal use. If you’re interested, do you know what the temperature for growing lettuce from seed in the greenhouse is? A greenhouse maintaining 70 to 75°F is best for optimal germination, but always remember the different lettuce requirements for a successful growing season. 

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How To Prevent Root Rot In Hydroponics: 3 Useful Tips

If you’re a newbie gardener who’s looking to find ways to hone your skills, you’d want to learn how to prevent root rot in hydroponics even before this problem affects your plants.

Hydroponics can be advantageous to crops in more ways than one. However, it also comes with risks of diseases, such as root rot, which can be destructive or even lethal to your plants.

Unfortunately, there are no effective methods to recover the wilted parts that were affected by the root rot once it hits your plants. The only thing you can do if you do not want this catastrophe to befall your crops is to prevent it before it happens. Read on to learn more about this subject.


What is Root Rot?

Root rot is a disease that attacks the plant roots and causes them to suffer decay. This usually happens when a lack of oxygen supply occurs in the substrate.

To give you an idea, think about plant roots that are submerged in water that only has a little oxygen in it. Over time, the plant suffocates and dies.

Aside from rot and decay, this disease also leads to the proliferation of fungi that are naturally present in the soil. These include Rhizoctonia, Alternaria, Pythium, Botrytis, Fusarium, or Phytophthora. As soon as fungi colonies start to grow, they tend to target the weakened roots and infect your precious plant babies.

Once the plant becomes infected, they won’t be able to take in what they need to grow – water, oxygen, and other nutrients. When this happens, it won’t be long before the plant dies.


What is Hydroponics?

In case you’re not aware, the term hydroponic is derived from a Latin word that means “working water”. To put it simply, hydroponics is an art that involves growing various types of plants without soil. If you’re like most people, the first thing that comes to mind when somebody talks about hydroponics would be a picture of plants with roots suspended into the water without using any type of growing medium.


Avoiding Root Rot in Hydroponic Systems

Detecting and identifying root rot can be tricky. When your plants get infected, their leaves and roots gradually wither until the whole crop itself dies from the lack of nutrients, which is a common symptom of many diseases.


What causes root rot in hydroponics?

One of the requirements in hydroponics systems is oxygen. Without it, your plants are basically on the road to death. On the other hand, lack of such is one of the major triggers for root rot, and it must be avoided at all costs.

Just like when planting in soil, you loosen up the ground so that your plants’ roots can have their required intake of oxygen. That is the case for crops grown in aqueous solutions as well. If they cannot breathe, they would not be able to grow.

Another agent for root rot is the temperature. The last thing you would want in your system are parasites that leech nutrients intended for your plants and infect the water during the process. In common terms, these fungi are called molds.

One of the best breeding grounds for these is warm and moist areas. For this reason, if the water temperature inside your reservoir is high, then you are susceptible to it. Something as minor as letting the solutions exposed to sunlight can already be a risk factor.


3 Useful Tips on How to prevent root rot in hydroponics

There is good news! Root rot in hydroponics can be prevented! Just follow these tips:

Tip#1: Use the right air pump

If you do not want root rot to affect your plants, you merely have to avoid its causes. If you need oxygen, keep the water bubbling by providing an air pump of appropriate size, and also give importance to proper ventilation in the room.


Tip #2: Maintain the temperature

The temperature should be maintained within the 70 to 80 degrees F range. Get rid of any materials that can make your system vulnerable to infections, and make sure not to disturb your crops while they are trying to grow.


Tip #3: Get rid of the rotten parts

However, if you failed in preventing the disease, then the rotten parts should be removed immediately. Cut them off as there is no chance of reviving them, and focus on the potential new growth instead. Fix your hydroponics system and eliminate the risks.


Why Give Greenhouse Gardening a Try?

Greenhouse gardening offers numerous benefits to greens aficionados who dare to take their gardening experience to the next level. Aside from acting as a shield against the effects of inclement weather, a mini, hobby, or semi-pro greenhouse can also serve as a protective layer that keeps harmful bugs and critters at bay.

What’s more, its enclosed structure allows you to control your plants’ growing conditions including the temperature, light, moisture, and ventilation of the greenhouse’s internal environment. With a controlled environment, you’ll be able to extend growing seasons and grow plants that aren’t native to your area.



No matter how well-informed you are about how to prevent root rot in hydroponics, you cannot completely eradicate the risks. Therefore, to avoid the worst-case scenario, you should be prepared to sacrifice the infected for the sake of others. While you’re at it, consider trying your hand at greenhouse gardening as well.


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