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Of all the vegetables take in , sugar has the highest per capita intake charge per unit in the United States , a astounding 23.4 pounds in 2021 . Leaf lettuce is the most democratic ( 54 % ) . The thermal dormancy of simoleons will prevent it from germinating if the soil is too warm or cold .

“Photo of several rows of green lettuces growing in a garden under the bright sunlight. The leaves are lush and vibrant, with shades of deep green and lighter green. Some plants have droplets of water on their leaves, suggesting recent watering. The background shows a natural outdoor setting."

Table of Contents

Growing Summer Lettuce

Lettuce is a high - value harvest , and in a public where one-year temperature are ever - increase , develop heating system - broad lettuce is a growing precedence . Unsurprisingly , the University of California is the leader in summertime lettuce research .

Lettuce is California ’s fifth - largest commodity , with a grocery value of over US$ 3 billion . Lettuce is a widely grown harvest worldwide , with different part favoring dissimilar varieties .

The average one-year lettuce consumption in the United States has dropped sincepriceshave rocketed to $ 3.58 per pound ( Average Romaine lettuce price in Dec 2022 ) . The United States export 3.6 million ton of gelt annually .

Close-up of a green lettuce leaf with curly edges, showing the texture and veins of the leaf.

China grows more lettuce than any other country , about 13.5 million tons yearly , in the main for local consumption , and Spain export just under a million tons annually .

Used as a garnish in most fast food for thought products , cabbage is in requirement , and finding solutions for growing shekels without the risk of early bolting is essential .

In 2015/16 , Sacromento ’s Fair Oaks Horticulture Center did some trials on lettuce bolt out times and temperatures . More recently , the University of Delaware and the Practical Farmers of Iowa ( PFI ) did similar tests .

A photo of a hydroponic system with rows of green lettuce plants growing in small containers filled with nutrient-rich water. The plants are arranged neatly in straight lines and illuminated by artificial lights above them. The background is dark and blurry, emphasizing the bright green color of the lettuce leaves.

We want to beat the passion and regain the most heat - resistant or heat energy - tolerant lettuce flora . My efforts are loose , and I trust you also push the bound , found what works in your sphere .

The Fundamental Temperature Needs of Lettuce Plants

Lettuce is a coolheaded - season vegetable , and seeds will germinate at 35 ° F/1.6 ° C , but the optimal dirt temperature is 70 to 75 ° F/21 – 24 ° C . The maximum temperature at which simoleons seeds will germinate is 85 ° F/29.4 ° C .

Extended periods of temperatures above 85 ° F/29.4 ° C will cause gelt to bolt , a common challenge to growing lettuce in summertime . If growing bread in summertime , see good afternoon shade , as too much sun is a bolt factor .

dinero seed needs light to spud , but plants do well with three to five 60 minutes of sunlight , avoiding the midday sun . Taller works can be grown as companions to purge some shade , though this is less potential during the middle of the day when the lettuce plants necessitate it most .

Rows of lettuce plants are visible in the foreground, thriving underneath a green shade cloth that covers the entire area. The lettuce leaves are a vibrant shade of green and appear healthy and well-nourished. The soil in which the plants are growing is neatly groomed and free of any debris or weeds.

Plant Bolting

Several garden vegetables a biennial plans grown as annuals . Biennial industrial plant grow rootage and beef up their foliage in class one to farm virile , resilient , healthy ejaculate in yr two .

The plants rush the seed production physical process when the environs alter ( more clean and higher temperature ) . gardener call it bolting , and it by and large refers to vegetable plants that begin flowering .

regrettably , bolting can diminish the quality of your harvest . Lettuce plants evolve a bitter perceptiveness as they dedicate more resources to flowering and seed output .

A close-up photo of Muir Lettuce leaves, showing their vibrant green color and delicate texture. Muir Lettuce is a sweet and flavorful variety of lettuce.

If you need to grow lolly in summer , face for “ slow abscond ” seed . Grow open - leaf varieties that permit you to reap out leave while the works is still young .

Remove drop plants to avoid volunteer lolly plant . put back spend plant life with unfermented lettuce plants to keep your summer garden vibrant .

Sowing Lettuce Seeds

Several blogger suggest verbatim seeding ; while possible , the risks preponderate any benefits . Lettuce works seeds are disease prone , and I send word gardeners not to produce seed from previous crop .

Instead , purchase your seeds from a reputable manufacturer that license their stock .

How to Grow Lettuce in Summer

Summer Site Selection

Please retrieve that turn lettuce in summer is set aside for coolheaded climates or controlled environments . There are several summer crop , but lettuce is not one of them . Avoid growing lucre in summertime in hot climates .

That said , cooler climate allow yr - round lettuce production , and I imagine it wo n’t be long before Washington State and other northerly states become significant producers . Washington State is already the second biggest veg crop manufacturer ( after California ) .

Lettuce may bolt in response to high-pitched - temperature strain , and the leaves may become sulfurous when the plant transitions to flowering ( see picture at correctly ) . If the plant becomes water stressed in red-hot weather condition , the leave wilt , toughen , and become bitter .

A close-up photograph of a green leafy vegetable, known as Skyphos lettuce. The lettuce has a crinkled texture and the leaves are slightly curled, giving it a fluffy appearance. The light shines on the lettuce from the top, highlighting its fresh and vibrant color.

Managing Summer Temperatures

To successfully arise lettuce in ardent weather , reckon the following strategies :

Please do not cool your growing moolah by wet leaves . Summer stress vectors bristle , and wet parting will cause rapid pathogen bedspread and diseases . Keep the stain moist and relaxed , the leaves dry , and the lettuce under a shade textile in the midday sunshine .

Lettuce: 7 Heat Tolerant Lettuce Varieties

All pelf bolt and those that do n’t may become blistering if exposed to gamey temperatures and long days of bright light . Heat tolerance is relative , but some varieties are slower to bolt in the summer heat .

Leaf lettuce allow early harvest home , and romaine lettuce has a report for being more warmth resilient . My mesa below lists 21 varieties , of which 10 are foliage loot and no Iceberg lettuce .

That ’s because loose - leaf lettuces have good air flow and heat dissolution mechanisms than head lettuces . That ’s a generalization because Romaine gelt forms question but is much less compact than iceberg , and unaffixed - foliage lettuce is one of the best warm - season variety .

“Close-up photo of a head of green Butter lettuce, showcasing its large, loose leaves with ruffled edges. The leaves are vibrant green and slightly curly, with a smooth surface and a soft texture. The lettuce is displayed on a white background, emphasizing its natural beauty. This variety of lettuce is known for its mild, buttery flavor and is a popular choice for salads and sandwiches."

Below is a mesa of 21 heat - tolerant lettuce varieties , with my selection of the top seven listed first and in monastic order of preference . Several warmth - tolerant choice are hybrids develop byJohnny ’s Select Seeds .

Muir Lettuce is a multifariousness that is somewhat sweet-scented and more flavorful than other types of lettuce . It is a hardy variety of lettuce capable of growing in many climate .

It has heavy , red-hot leaves with a clean dark-green color and a hint of bronze . The leaf are also very crisp and have a mild , slightly dulcet flavour . Muir lettuce is ideal for salad , sandwiches , wraps , and other recipes .

“Close-up of Salanova® Red Butter lettuce leaves showcasing their dark red color, loose head shape, and delicate texture. The lettuce variety was developed by Dutch seed company Rijk Zwaan and is known for its sweet flavor."

It is also a large dietetic fiber , vitamin , and mineral source .

Muir gelt is exceptionally tolerant of hot days , and trial run have repeatedly been the slowest to bolt . Only buy seeds with certified resistance to downy mold and bushy love apple stunt virus ( lettuce dieback complex ) .

Skyphos bread is a loose - leaf lettuce with a unique , crinkled grain and a sweet and mild flavor . It is famous for salad greenness , sandwiches , wraps , and garnishing denture .

A photo of a head of Sunland lettuce, a type of romaine lettuce grown in the San Joaquin Valley of California. The lettuce is vibrant green with long, crisp leaves that curl slightly at the edges. The head of lettuce is surrounded by other lettuce plants in the background.

Skyphos lettuce is relatively easy to grow and can be glean in as niggling as four hebdomad . The flora is deep green , and the leave are thickset and cranky .

It is also very resistive to beetle off and can raise in various temperature , making it an excellent pick for multiple climates .

Salanova ® Green Butter lolly was develop by the Dutch fellowship Bejo Seeds in 2005 . Salanova ® Green Butter lettuce is a large , loose - leaf with a balmy , buttery flavor , and it is an excellent pick for salads , sandwich , and wrapper .

“Fresh green Sparx lettuce leaves arranged on top of a rustic brown wooden table. The table’s natural wood grain and texture add warmth and contrast to the vibrant green lettuce leaves, creating an appealing visual composition. Sparx lettuce is a nutrient-rich and flavorful variety of lettuce that is a great addition to any healthy meal."

The leafage are divided into section , giving the lettuce its distinctive flavor . Salanova ® Green Butter dinero is also known for its gamy content of vitamins A and C and other essential vitamin and minerals . This lettuce variety is easy to grow and maintain in the home garden and is resistant to bolt .

Salanova ® Red Butter shekels is a diversity of dough developed by the Dutch seed company Rijk Zwaan and has a dark carmine colour , a sweet flavor , and a loose heading embodiment .

The leaves are slightly crunchy and have a balmy , larder taste . Salanova ® Red Butter clams is famous for salads , sandwich , wraps , and other dish , and it is also a great author of vitamins and minerals .

A photo of a green lettuce leaf with frilly edges, sitting on a white background. The lettuce is a Casey Lettuce, a hybrid variety of lettuce that was developed in Australia.

Sunland loot is romaine grown in the San Joaquin Valley of California . It is a gamey - quality variety well - suited for salads , sandwich , and wraps . Sunland lettuce is create in a unique surroundings that combines the idealistic soil , clime , and irrigation .

This combination produces a singular flavor and texture unmatchable by other lettuces . Sunland lettuce is also known for its high-pitched nutritional note value , load down with essential vitamins , mineral , and antioxidant .

Its high nutritional content is why it is a popular choice for wellness - witting consumers .

Sparx lettuce is a unique salmagundi known for its high levels of aliment and flavor . It is a chicory family phallus and is a hybridisation between crisphead lettuce and romaine cabbage .

It has a shining , frizzy grain and a odoriferous , nutty flavor . It is rich in vitamin A , C , and K , vitamin M , Fe , and calcium . It is also a adept source of dietetical fiber . Sparx lettuce is a popular choice for salads , sandwiches , and wraps .

Casey Lettuce is a hybrid variety of lettuce developed in Australia . It has a medium - immature leaf with a firm , crunchy grain and a sweet , meek flavor .

Casey Lettuce is one of Australia ’s most democratic variety show and is also grow in New Zealand , the United States , and several other state .

It is commonly used as a salad green but can also be eat cook or a topping for sandwiches . Casey Lettuce is a nerveless - season crop , best planted in the other leap or previous summer .

FAQs on The Best 7 Lettuce Types to Grow During Summer Months

Can you produce lettuce all summer?Lettuce is a coolheaded - season craw , but grow it in summer in cooler climate or controlled environmentsis possible . Planting slow - bolt lettuce assortment and provide good afternoon tone can help prevent bolting .

What lettuce is easy to grow?Loose - leaf lettuce is considered the easiest to raise because it requires less sustainment than other varieties , and you may reap the leaves while the works is still new . Also , loose - foliage lettuce tends to be more resistant to bolting , a common challenge to originate lettuce in summer .

Which lettuce lasts the longest?Romaine loot generally lasts the recollective among lettuce varieties . This moolah character can stay clean for up to two weeks when store aright in the refrigerator . However , it ’s essential to observe that the length of service of wampum also count on its novelty at the time of leverage , proper warehousing , and the temperature and humidness of the environment .

In Closing

If you implant lettuce in early spring , you could shell the heat and get a craw mid - summertime . If your local climate is warm , you must use every imagination to keep the dough plants cool enough not to bolt .

Shade material , mulching , persistently damp territory , and a airless centre for pestis are some tasks that are less important in coolheaded weather .