Jump to content
Strain Hunters Forum
Guest Guest guest user
Existing user? Sign In  

Sign In

Or sign in with one of these services

Sign Up
Search In
  • More options...
Find results that contain...
Find results in...

Search the Community

Showing results for tags 'cannabis cultivation'.

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • Test Area 2020
    • Testers Grow Journals ¡NEW Strains!
  • Welcome to Strain Hunters Forum
    • Introduce yourself
    • FAQ & Rules
    • Strain Hunters Live
    • News & Announcements
    • Suggest a future destination
    • Chill Out Lounge
  • Grow Area
    • Grow Journals Indoor
    • Grow Journals Outdoor
    • Grow Guru - Advanced Techniques
    • Grow Questions
    • Hash, Oils & Creams
    • Weed Infirmary
  • Strains & Nutrients testers
    • Testers Rules
    • Test Area: White Rhino Contest
    • Test Area: Cheese x White Widow & Super Bud x Train Wreck
    • Slex & GH Kush Test
    • Official Nutrient Testers
    • Damnesia - Official Seed Test
    • Afgooey - Official Seed Test
    • Caboose - Official Seed Test
    • Kalashnikova Auto - Official Seed Test
    • Money Maker - Official Seed Test
    • NL Auto - Official Seed Test
    • Skunk Auto - Official Seed Test
    • Sweet Mango Auto - Official Seed Test
    • White Lemon - Official Seed Test
    • White Strawberry Skunk - Official Seed Test
    • Other test
  • Photos for social networks (IG,FB,...)
    • SHARE your Photos for social networks here
  • Medical Cannabis
    • Medical Strains
    • Cannabis Extraction Methods
    • Doubts and real stories
  • 420 Talk
    • General Chat
    • Gear Reviews
    • Amsterdam
    • Flower Pictures & Videos
    • Cannabis laws & regulations
    • Cooking with Cannabis
    • Strains
  • Strain Hunters Contests
    • Current Contests
    • 3º Mega Contest
    • Share & Win
    • Indoor Cannabis World Cup
    • Outdoor Cannabis World Cup
    • Autoflowering Cannabis World Cup
  • Sección de habla Hispana
    • Presentaciones
    • I+D+I Testers, nutrientes, nuevos productos...
    • Cultivo en interior
    • Cultivo en exterior
    • Enfermerí­a cannabica
    • Hash, BHO, Jelly & Cocina cannabica
    • Eventos, noticias, actualidad
    • Fotografía Cannabica
    • Zona de ocio
  • Other languages Forum
    • German language
    • Italian language
    • Russian language
    • French language
    • Others language
  • 3º Mega Contest Green House Seeds Co.


  • Articles
    • Strains
    • Landraces
    • Franco's tricks
    • Many countries, one plant
    • Worldwide cannabis: many ways to use a plant
  • Expeditions
  • Miscellaneous
    • Media
  • Press releases


  • admin's Blog
  • franco's Blog
  • elektro's Blog
  • seedfinder's Blog
  • BomBholenat's Blog
  • Djkane4life's Blog
  • Me and the world!
  • tongyouo's Blog
  • alexnew's Blog
  • heminsi's Blog
  • chofay's Blog
  • Getting high again after a long hiatus
  • Flail's Blog
  • kissyou's Blog
  • News from Paradise
  • Potent's New beginnings
  • lixu007's Blog
  • booming's Blog
  • susanyue's Blog
  • simona's Blog
  • rainlly's Blog
  • HC01's Blog
  • Symptoms of Nutrient Deficiencies
  • aideconr's Bloggzgz
  • deryyere's Blog
  • geryihee's Blog
  • medman's Blog
  • mariobin's Blog
  • hujh2012's Blog
  • Problem with BB autoflowering
  • 2012 - Guerrilla Mountain Grow
  • tosh79's Blog
  • nickgreece's Blog
  • sourabh.libra28's Blog
  • CannabismanARG's Blog
  • MR.Cheese's Blog
  • PhenoHunter's Blog
  • Rockeymtngrower1's Blog
  • Rockeymtngrower1's Blog
  • Huntil's Blog
  • piffawana's Blog
  • MaryJanesFlowers' Blog
  • growtobepro2012's Blog
  • growtobepro2012's Private Blog
  • Ziommbell's Blog
  • rockwollerton's Blog
  • Growers with Units available
  • Chronic Grower's Blog
  • Potent's Blog
  • reane's Blog
  • Ernesto957's Blog
  • oroboros' Blog
  • Jungleman3030's Blog
  • reiska84's Blog
  • MR.Cheese's Blog - LIBERTY HAZE
  • Pi2's Blog
  • LED grow light Blog
  • gtbud's Blog
  • kgreenfinger#1's Blog
  • Figge's Blog
  • Aus42088's Blog
  • 2013 - 2nd Guerilla Mountain Grow - Shoreline
  • jman_420's Blog
  • sean351's Blog
  • uk silverback's Blog
  • Nike Free Run Tilbud
  • Nike Free 5.0 Outlet 
  • weshbud's Blog
  • Ragnarök Blog
  • Michael Bravin's Blog
  • Snoogan's Blog
  • Tokage's Blog
  • indo/man's Blog
  • cable's Blog
  • flower-lover's Blog
  • tribble's Blog
  • tribble's Blog
  • GianlucaZizzari's Blog
  • Make it Legal Blog
  • Dr Zulu's Blog
  • Haze
  • 420Geezer
  • Buy weed online in US
  • EastCoastCannaCure's Multiple Tent, Multiple Strain, HPS vs LED Perpetual Tester Grow
  • blogs_blog_101
  • Weed, Moon rocks , Cannabis Oil For SALE
  • i need help
  • i need help
  • Trust growroom
  • Beach flag design 
  • marisha
  • Great Sativa strains Delivery (Sour Diesel, Jack Herer, Ambulance, Charlottes Web)
  • Buy Weed Online Canada
  • Johnnywong
  • Rosemary
  • Nepal Trip - LedCherryBerry
  • Megabud Store Online
  • How Does Marijuana Kill Cancer Cells?
  • Vma
  • Medical Cannabis Oil Online
  • https://listofdiet.com/arouza-male-enhancement/
  • https://medicfitonline.store/instant-keto/
  • What are the tips to grow autoflowering cannabis seeds?
  • http://medicfitonline.store/vitariche-luxe
  • http://medicfitonline.store/
  • http://medicfitonline.store/
  • @shawn00
  • Perfect green coffee capsules for appetite suppressant
  • https://www.topbodyproducts.com/immune-defence/
  • Research chemicals
  • Chemicals
  • Chemicals BB
  • Was ist eine Kolophoniumpresse? Wie funktioniert sie? - 420 Guide
  • Was ist eine Kolophoniumpresse? Wie funktioniert sie? - 420 Guide
  • De ECO Farm Kit 150W CMH-evaluatie
  • ECOFarm
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • Ficher Chem Co. Ltd: Buy Research Chemicals Online
  • Buy weed online |Weed for sale |THC oil for sale Visit: http://cannabis420stores.com
  • The 3 Mistakes of My Life: Amazing Book Summary

Find results in...

Find results that contain...

Date Created

  • Start


Last Updated

  • Start


Filter by number of...


  • Start





Website URL







Found 8 results

  1. Buy yourself some fertilized potting soil in early June.Although not usually organic, this is the easiest way to do it.This pot soil would be best, given that plants may not adapt to certain conditions.It must have: Enough nutrition.If you pick up a bag and it says," n-p-k = x % -y % -z %," these data indicate the level of nitrogen, phosphorus and potassium in the soil. PH is between 5.9 and 6.5.Of course, you can change it yourself.Even organic fertilizers you buy at the store tend to have a low pH.[6]. "" "Fill a small paper cup with enough soil to go all the way to the rim.To moisten the soil, bury the seeds about a centimeter (1/2") deep.Do this for each seed.Place the cup in a warm (about 70 °F (21°C) sunny place. Water the plants and keep them warm.When your plant sprouts, keep the soil moist and allow it to grow until the roots are set.The whole cup will be taken up by the roots, and the plants and soil will remain in the shape of the cup when removed as a whole.
  2. Outdoor planting sites are important.Choose your planting site.To have a successful harvest, it is often important to choose the right place.You don't want them to be disturbed by humans, and you don't want them to be disturbed by animals, so choose your location carefully.Look for a place that you can reach but that is not obvious.Consider the following factors: A good and reliable water source is necessary.A location near a river or stream is ideal, but keep in mind that there is a risk of flooding in spring and autumn.Look for a trail of water high in the water, in the forest, or on a rock. Avoid areas where pine trees grow -- the soil in such areas may be too acidic;Look for grassy hillsides and see what else grows on them.If there is enough grass, weeds, and nettles, the place is likely to have good soil and water.Woodlands are also worth considering, but consider that sunlight reaches the plants through the canopy.As you explore the site, think about how it will change over the next few months.In the summer, temperatures will get hotter, sunlight will get stronger, and your plants will probably get roasted more than they do now. Find a place where your plants get at least five hours of direct sunlight each day, where does the sun shine in the morning and where does it shine at night?What happens when the seasons change? Land preparation.The easiest way is to start small -- about 10 feet apart.That sounds like a lot, but there's only five feet of space on either side of the leaf.Remember, they can grow up to 1.5 meters tall! Remove weeds nearby and dig holes of the right size.They should be at least 2 feet deep and 2 feet wide.It's best to use your own clean soil from the garden supply store, which also sells compost and compost.Virgin woodland soils often contain high levels of pests and disease and may not be of the best quality.It is best to cover the planting area with a thick film to keep moisture below the ground. " Plant seeds.Planting should be done at the beginning of the season, around April or may, after the last frost.Obviously, the timing will depend on where you plant it.If you're in the northern hemisphere, it's the turn of spring and summer. Spring in the southern hemisphere begins on September 1 and needs to wait for a warm period after that date.Cannabis plants don't tolerate frost, so it's best to avoid it for safety. Plant the seeds of the plant, using the sides, and insert the seeds about 1.25 cm (1/2 ") into the soil you have prepared.Make sure they're watered, and make sure the sun doesn't get too dry.Also, make sure they're always moist.After about 48 hours you should start to see the seeds open and then the buds will come out. Provide your plants with a constant supply of water.The best solution would be to have a stream, river or lake nearby and attach a solar pump with a timer.This is the best way, not the easiest.Water the plants every morning and evening. Another solution is to design your own core system, as discussed earlier.Drill a hole the size of a half a pea into the bottom of a 5-gallon (18 liter) or 10-gallon (or more) bucket or plastic container.Place the bucket next to the plant and use a cloth or cotton string to transfer water (or nutrient solution) from the hole in the bucket to the soil near the plant. You should be sure to provide the right amount of water.Too much water and your plants will drown (you'll see the leaves turn yellow);There is too little water for them to grow.Ultimately, you should use about 20 to 40 gallons (75 to 150 liters) of water per season.It all depends on the type of soil you use and the amount of light your plants receive to adapt. Add fertilizer to your plants.Once the seedlings are planted, they quickly enter a vigorous vegetative growth stage.From such a fragile beginning, plants quickly become whole and strong.It would be nice to add some nitrogen fertilizer to your plants at this stage. Unlike growing marijuana indoors, where you can't control the duration of the vegetative growth phase, the plant may grow larger in the summer.But at least there's no pot in your room. After about three weeks of planting, remove the weeds around the plant.If your plantation is in the wilderness, threatening weeds will soon take over the land and drain your lovely seedlings.You don't need to burn them in the first place, you just need to clear the area around each plant about 3 feet (1 meter). Repeat the process about 3 weeks later.You may need to do it again in 3 weeks, depending on your area.Most plants, at this point, are strong enough to make room for themselves and defeat the weeds. If something bad happens in the weather, check your plants for damage.Strong winds, rain, and drought can all undo your efforts.However, don't give up, these plants can save themselves, so don't panic if you're in an area with bad weather. Identify plant sex.While it's often tricky to identify the sexes of marijuana, it's easier if you gain more experience.The reason for identifying the sex of a plant is that you can then remove the male plant before it pollinates the female plant.If pollination is successful, female plants will begin to grow seeds, which will distract them from producing THC. At the end of summer, with fewer daylight hours, the change in light will trigger your plants to bloom.What you need to look at is the preflowering characteristics of the branches where they join. Male anthesis should be easier to discern, but a magnifying glass makes it easier to see.Male flowers form at the junction of branches and stems, and pollen sacs form small balls.Remove the male plants." Pay attention to flowering.The female flower will begin to form coke balls at the junction of branches, with the largest one at the top of each plant.And if you look closely, you'll see pods, and they expand;Or pods will carry seeds (if your plant has been pollinated) or fake pods containing THC (if you have removed the male plant). When the flowers are ready to harvest, the flowers begin to darken and the pod pistil becomes swollen and sticks to the resin and THC trichome.Once most of the buds have darkened, you should be ready to harvest! Harvest your plants.Plan it all out, because if all goes according to plan, you risk coming home with a bunch of smelly, sticky buds.If possible, it's better to do it at night (you know).Ideally, you can harvest when the buds are dark, swollen, and loaded with THC crystals. However, field planting is not always ideal, so pay attention to weather forecasts.If you have extreme weather or worse, like a frost coming up, and your plants are already in bud but not yet fully ripe, it's worth harvesting.This needs to be done on a case-by-case basis, and there is no single guideline that covers all the results. Harvest the buds with a clean, sharp knife.Often discarded fan leaves work, though some growers use them for cooking. Dry your pot.Don't spoil it with impatience now!It can easily happen!The best smoke comes from buds that are slowly dried.Hang the buds separately in a cool, dark, well-ventilated place.Let them dry naturally in about 5 days. Some growers use microwave ovens to dry plants, but this is bad for the quality and taste of the smoke.Don't do that. Grow marijuana outdoors. Build a small fence around your area with barbed wire to keep rabbits and deer out.The smell of urine also keeps wildlife away, so you can use it to water the land every time you go.
  3. First, seed selection is an effective measure to cultivate early seedling, qi seedling and strong seedling. The seeds used for sowing should be selected by wind and screened to remove the flattened seeds, tender seeds and impurities. The seeds with full, high 1000-seed weight, uniform size, fresh color and high germination rate should be selected as seeds to achieve the requirements of improving the emergence rate and the full seedling.According to investigation, use mature bad or 1000 seed weight low seed sow, germination rate reduces 20% - 25%, seedling is not neat, seedling is emaciated, easy to infect disease insect, and small hemp rate is high.Sowing with the old seed (seed coat is dark green) every other year, the germination rate is greatly reduced, will cause serious seedling lack and ridging. Hemp seeds can germinate at low temperature (1-3 ℃), and its seedlings have the ability to endure short low temperature, so the sowing time range in various hemp areas is relatively large.From the perspective of the sowing time of hemp in different places, there are great differences due to the differences in climate, soil, varieties and crop rotation systems.Liaoning is sown in early April, jilin and heilongjiang in mid-april, late April and early may. The sowing time of hemp is related to different purposes of cultivation and utilization.When collecting hemp to cultivate, generally timely early sowing;However, in order to make the mature stage of seed irrigation slurry under the cool climate in autumn, seeds are generally planted later.Sowing time and local harvest when the wet hemp water temperature.Hemp is sown when the soil temperature rises above 5-250px to 8-10 ℃, from sowing to emergence for 10-15 days.In this case, sowing as early as possible, seedling period long, roots roots deep, can play the role of cultivating strong seedlings.Miao zhuang laid a foundation for rapid growth, which accelerated the growth of hemp plants, neat the population of hemp fields, increased the effective number of plants, improved the hemp yield and increased fiber yield.Early sowing, fast growing and timely early harvest, using the warmer water temperature ouma, achieve high yield and quality, high economic benefits.Accordingly, hemp is timely and early sow, want to notice the temperature of the ground when sowing temperate and rapid growth period already (19 -- 23℃), give attention to even the water temperature that the place asks when retting hemp (20℃ above), only 3 person are very good union, ability has integrated effect. There are three ways of sowing hemp in different places: spreading, drilling and vod.Seed collection and cultivation are commonly used on demand, as well as drill and broadcast.Hemp cultivation is usually spread and drill.Fiber hemp is suitable for close planting and should be drilled in area cultivation.Seeding has the advantages of even seed, uniform sowing depth, neat seedling emergence and convenient field management.
  4. From January to April (1) site selection: sandy loam with deep soil layer, strong water and fertility retention, soft and fertile soil and good drainage is good, and its pH value is 6-6.5 slightly acidic. (2) rotation: rotation with rice, vegetables, jute and other crops can reduce diseases and insects and improve the storage capacity. (3) preparation: the hemp should be ploughed deeply, with a depth of up to 30 cm and a width of 1.0-2.3 meters. (4) fertilization: 3/4 of hemp nutrients must be absorbed at the early stage of growth, but at the seedling stage, the roots grow slowly and the absorption capacity is weak. Therefore, sufficient base fertilizer should be applied, such as general manure, manure or green manure 1500-2500 kg, and plant ash 40-50 kg, etc.. (5) seeding: seed standard: pure and full, full and complete, no pests and diseases, uniform size, fresh color, high germination rate, small seed and large seed 1000-grain weight should be more than 20 grams and 25 grams, germination rate of 95%, containing no more than 5% impurity rate.You don't have to age your seeds every other year.Rinse the seeds with water before sowing, soak them in water for 2-3 days, take them out and expose them to the sun for 1 day, and sow them again.Early sowing at the right time is the key to increase production. Generally, sowing can be done at above 8℃ of ground temperature in our province, and it can be done in December to April of the next year, but most of the sowing is done in 2-3 months.Yield per mu is 1 kg.The sowing quantity of fiber hemp is larger than that of seed hemp.Early ripening seeds were more important than late ripening seeds, spreading seeds were more important than strips and vod, wide strips were more important than narrow strips, and fat fields were more important than thin fields.Generally broadcast or drill.Sow the seedlings with a spacing of 10-17 cm and a number of plants of 80-100,000.Drill plants with spacing of 7 cm, row spacing of 13 -- 26 cm, leaving 20-30 thousand seedlings.Sowing depth 1.7 -- 3.3 cm. April to July (1) thinning, fixing and replenishing: thinning is carried out when the seedling height is 3cm for the first time and 7cm for the second time when there are 2 pairs of true leaves.When the seedlings appear 3 pairs of true leaves and are 10 cm high, the seedlings can be fixed according to the specified plant spacing.In addition, when the hemp height is 0.7-1.3 meters, the weak seedlings are pulled out again.Mu leaves the seedling density our province to be in 2-3 thousand plants, the early maturing seed, the fat ground is compared to the late ripening seed, the late sowing, the thin ground density is big, the thread hemp density is bigger than queerflax. (2) cultivation: hemp seedlings grow slowly and are vulnerable.Intertillage weeding should be carried out before the vigorous growth stage of stems, and combined with seedling thinning for 2-3 times.The ploughing depth is first shallow and then shallow.Seedling height 7-10 cm is shallow hoe 7 cm, seedling height 17-20 cm is deep hoe 10-13 cm.Seedling height of 30 cm above and shallow hoe 3-7 cm.Prevent the hoe from hurting the fine roots.Loosen soil immediately after rain, prevent soil consolidation: (3) fertilizer application: the topdressing is mainly rapid-effect nitrogen fertilizer, 5-10 kg of ammonium sulfide or 500-1000 kg of human excrement or 25-30 kg of oil cake, which should be applied in 2-3 times in combination with seedling thinning, seedling fixation or before sealing. It should not be later than the maximum extension of hemp stem. The rapid-effect nitrogen, phosphorus and potash fertilizer should be added before flowering of hemp. (4) soil raising: generally, soil raising is carried out 2-3 times in combination with intertillage weeding and fertilization to cover the fertilizer, deepen the furrow and prevent lodging. (5) irrigation and drainage: timely irrigation is needed during the long period of hemp flourishing and drought.Seedling stage growth is slow, the root system development is slow, head water should not be too early, so as not to affect the root deep roots.Our province is rainy, but also should pay attention to drainage, water. (6) wind disaster prevention: due to the tall stems of hemp during its growth, it is easy to be affected by wind disaster. Therefore, it is necessary to prepare the ground carefully, cultivate strong seedlings, irrigate head water late, and irrigate lightly and frequently.Nitrogen dressing to increase phosphorus and potassium fertilizer;Choose the measure such as stem firm breed. (7) pest control: there are many cannabis diseases and pests.Diseases such as white star disease, dew fungus disease, brown spot disease, white spot disease and sclerotinia can be mainly prevented and controlled.Pay attention to drainage;Three elements of NPK were applied together.Implement crop rotation;Pay attention to field ventilation and light transmission;Spray bordeaux mixture and other methods of prevention and control.The main pests are jumping beetle, small weevil, etc.Remove weeds from the field;Killing and luring adults;Implement crop rotation and other control methods. July to September (1) harvest: about july-august harvest of fiber hemp;About September the harvest was for growing cannabis. (2) harvest criteria: the middle and lower leaves of the hemp plant fall off, the stems and leaves are yellowish-white, and the upper stems and leaves are yellowish-green or when the male flowers are in full bloom and the female flowers bear small fruits.It is best to harvest in different stages of maturity.
  5. The pest of hemp still has corn borer, north Korea black beetle, mole cricket, ground tiger, needle worm, snail, build bridge bug, armyworm to wait.Mole cricket, ground tiger harm seedlings, can kill or heap grass plus toxic bait kill;Snail makes hemp leaf and hemp tip stick together, inhibit growth, can spray lime liquid poison, other pests such as the occurrence of serious pesticide control. Other diseases of cannabis include: blight of cannabis, dew fungus disease of cannabis (also known as downy mildew), root nematode disease of cannabis, blight of cannabis, blight of cannabis, blight of cannabis, blight of cannabis, blight of cannabis, blight of cannabis, etc. However, the diseases are not common and serious. Hemp plagiodera A bronze - green beetle.The worm body length of 1.8-2.6mm, thick russet tip of the wing sheath, leg segments are very developed, good at jumping.The adults of the leaf beetle overwintered at 1 -- 37.5px in the soil or at the leaf, grass, plant residues and soil cracks.The adults nibble cannabis leaves into many holes, affecting the growth of hemp plants, and also nibble inflorescences and immature seeds, causing serious damage to the seedling stage. Control methods: in addition to the use of chemical pesticides for control, can also be used to eight-leaved roots and locust roots and leaves 0.5kg, add 2.5kg of water to boil for one hour of liquid spray kill;The harm can be mitigated by crop rotation and weed removal. Small weed weevil This insect eats hemp only, the adult is harmful to hemp insect, hemp sheath and axillary bud, cause hemp plant to stop growing, from axillary bud send branch, form double head.The adult beetle is a small grayish-brown beetle with a body length of 2.3 -- 2.8mm and a body width of 1.4 -- 1.9mm. It is oval in shape and has a very long muzzle. The abdomen end of the male insect is slightly round.The larvae are milky white and curved like a crescent.The mature larvae are yellowish-white with a body length of 3.3-3.8mm.The chrysalis is milky white, 2.35-2.8mm long, hidden in a circular cocoon of earth. Control methods: should be mastered in the adult just unearthed before laying eggs before pharmaceutical control. Marijuana sawyer, Hemp plant is easy to break in high wind, hemp skin is broken, fiber production, quality reduction.Adults are dark brown, cylindrical beetles, chest and shoulders with two white bands;Overwintering with larvae;They become adults between June and July.Larva burrows into hemp stem to eat, gradually move to the base of hemp stem, insect dung traces at the mouth. Prevention and cure method: burn hemp root, hemp stem.Drug control in late June. Brown spot of cannabis Most occur on the old leaves, the surface of the first leaf appeared, dark brown spots, after the spots expanded into a round or near round, the central part into light brown, around pale yellow, back dense gray mold.This disease mostly occurs in July and forms early leaf litter when the damage is serious. Prevention and control methods: three elements of nitrogen, phosphorus and potassium fertilizer used together to enhance the disease resistance of hemp plants;Come on when gush bordeaux fluid 2-3 times. Sclerotinosis of cannabis It can occur in the whole growth period, and it can happen most quickly under high temperature and wet conditions.Generally, when the seedling height is 750px, the irregular pattern of grey-black disease spots occurs at 250px above the ground, gradually expanding and densely growing black-gray mold, and the seedling will break off and die.When the plant grows to more than 1m, the leaves appear irregular yellowish-white plaques with many black rat droppings of sclerotia. Prevention and control methods: remove the diseased plant burning grass;Onset of the initial spray of bordeaux fluid 2-3 times. White star disease of cannabis The disease occurs in the leaves.At first the surface of diseased leaves has small yellowish-white or yellowish-brown spots along the veins, elliptic or triangular, about 1mm long.After that, the disease spot expands and connects with neighboring disease spot to form large 4 -- 8×3 -- 5mm disease spot.The center of the spot becomes a black or off-white powdery substance, and the surrounding parts are grayish brown or yellowish brown.The early deciduous leaves and stunted growth will affect the yield. Prevention and treatment: remove the diseased leaves and burn them;Pay attention to drainage;Onset of the initial spray of bordeaux fluid 2-3 times.
  6. Hemp has different requirements on temperature with different varieties. Generally, from sowing to maturity, the accumulated temperature of which is greater than or equal to 0℃ is 1900-2000℃, and that of which is 2700-3000℃.For early maturing varieties, the accumulated temperature of 1600-1700℃ can reach the process maturity.Hemp seeds can germinate when the soil temperature is above 1℃, but the seedlings should be orderly, generally it is advisable to sow when the soil temperature is above 8-10℃.The optimal temperature for germination of hemp seeds is 25-35℃, and the highest temperature is no more than 45℃. However, the seeds germinate quickly and evenly when the temperature is high.Hemp seedlings can tolerate -5 low temperature in a short time, but its growth process will be seriously affected. Suitable growth temperature, seedling stage is 10-15℃;The rapid growth period was 18-30℃, and 19-25℃ was the most suitable.After flowering, the seeds mature to 18-20℃, and the flowering stage meets the low temperature of -1℃, the flower apparatus is damaged, and the flower apparatus dies below -2℃, especially male flowers.Seeds can withstand low temperature and lower temperature of 3-5℃ within 10-15 days after germination;At a low temperature of -5℃, its growth will be delayed a little.However, if adequate water and nutrients can be supplied, the low temperature in seedling stage has little effect on later development and yield.In 1957, after the emergence of hemp seedlings in the main hemp producing area in shandong, the growth of hemp was not affected when it was frozen in the shower. Northern shaanxi province has the habit of sending seeds the first winter.Winter sowing experiments in heilongjiang and jilin provinces were successful.All these indicate that cannabis plants have a strong ability to resist low temperature at the seedling stage. Hemp is not tolerant to low temperature during flowering, and it is easy to die when it encounters sub-zero low temperature during flowering, especially the male plant dies more.During the growth period, the average temperature of day and night has a great influence on the growth of cannabis, especially from bud to the end of flowering, the growth of stem is the fastest and dry matter increases greatly.During this period, the optimal temperature should be maintained around 16(night)-25f (day).
  7. Cannabis requires the most nitrogen, potassium and phosphorus, followed by potassium. For the yield of 1 ton of hemp stalk per hectare, it requires 15-20 kg of nitrogen, 15-20 kg of K2O and 4-5 kg of P2O5.The results showed that the fresh stems and leaves of hemp contained 0.525% nitrogen, 0.133% phosphorus and 0.415% potassium.Fresh stems contained 0.473% nitrogen, 0.111% phosphorus and 0.341% potassium.Fresh leaves contained 0.858% nitrogen, 0.275% phosphorus and 0.891% potassium. When marijuana is given sufficient nitrogen, phosphorus and potassium fertilizer;The formation of fibers in the stem is most intense.Nitrogen plays the largest role in the composition of complete fertilizer.In the absence of nitrogen, the effect of phosphorus and potassium fertilizer on fiber formation appears weak. Therefore, to improve the fiber formation process, early nitrogen application is very important.Application of nitrogen in late stage had little effect on the formation of primary fibers, but increased the formation of secondary fibers.Apply nitrogen too much, fiber becomes coarse, strength decreases, still can cause disease. Many experimental studies have proved that the combination of nitrogen, phosphorus and potassium is better than the single application of nitrogen fertilizer.The effect of increasing yield is more remarkable when n, p and k are used together.This is because phosphate fertilizer has the effect of improving fiber quality and seed yield, potash fertilizer has the effect of improving fiber yield and quality, and seed oil content, potassium affects fiber quality more than phosphorus, and phosphorus deficiency affects nitrogen absorption.It has been proved that the combination of chemical fertilizer and farm organic fertilizer plays an important role in increasing fiber yield and varieties. The absorption of nitrogen, phosphorus and potassium in different growth stages of cannabis is different.Hemp needs a lot of nitrogen fertilizer in the whole vegetative growth period before flowering, especially in the first 6-8 weeks when nitrogen absorption is concentrated, but too much nitrogen is unfavorable to fiber content and fiber strength.Cannabis needs a steady supply of phosphate fertilizer throughout the growth period, and the demand for phosphorus continues to increase until flowering, and phosphorus can promote the effective absorption of nitrogen by cannabis.From germination to harvest, hemp's potassium requirements continue to increase, reaching a maximum during the fiber formation period.Potassium fiber quality is more important than phosphorus. There are differences in the absorption and utilization of nitrogen, phosphorus and potassium in different types of cannabis.Generally, the absorption and utilization of nutrients of early maturing hemp are not balanced, and the absorption of nutrients in the first two months accounts for 3/4, while most of the nutrients are consumed in the short period from bud to blossom.The absorption and utilization of nutrients of late - ripening hemp were more balanced.The absorption of nitrogen and potassium reached a peak 20-25 days after sowing early hemp.The male plant absorbed more nitrogen than the female plant from the seedling stage to the pre-flowering stage.The female plant absorbed more nitrogen than the male plant at the flowering stage. Some trace elements such as copper, sodium, boron, manganese and zinc have certain effects on hemp growth and fiber quality improvement.Practice has proved that potassium, manganese and magnesium have the greatest influence on hemp yield and fiber development. Manganese, magnesium and potassium 10 magnesium increase production by 27-30%, and potassium and potassium 10 manganese increase production by 15-17%.
  8. Hemp is a tall stalk crop, which consumes a lot of water. Every kilogram of dry matter needs to consume 300-500 ml of water, which is 1.5-2 times more than wheat and oats, and 3 times more than corn. Water deficit in cannabis leaves increases the content of carotenoids including lutein, so leaves turn yellow and photosynthetic capacity decreases.Hemp is resistant to atmospheric drought but not to soil drought, so irrigation is particularly effective. In the whole growing season of hemp, precipitation of 50-70cm is needed. In the germination period and the first 6 weeks of growth period, soil moisture should be adequate. In the rapid growing season (column height increases by 4-6cm/ day), soil moisture should be high. Hemp grows faster in the case of late sowing than early sowing, and the water consumed in the main growing season accounts for 80-90% of the total water demand.Therefore, increasing soil moisture during this period had a significant effect on yield.Light rain in the mature stage can increase seed yield.When the stem height is 50-70cm, it is tolerant to drought, but the drought and high temperature will promote early maturity, plant height will decrease, and yield will be low.However, too much rain in the flowering period to the male plant mature, which is easy to cause mildew and blackening of the stem, is not conducive to the female plant seed grouting. Hemp growth during the waterlogging, hemp field waterlogging two days will cause hemp plant death.Soil moisture not only affects fiber yield and quality, but also affects the content of cannabinol.When the soil moisture content of hemp plants was 40%, 60% and 80%, the radius of cortex and xylem, the number and diameter of primary fibers and the yield of stem and seed of both male and female plants increased with the increase of soil moisture.When soil moisture is equivalent to 70-80% of the total water capacity of soil, fiber yield is the highest and quality is the best. The amount of water demand of hemp is related to the nutrient conditions in the soil. Under the condition of good fertilization, the water demand is 575-985 cubic meters, while under the condition of poor or no fertilization, the water demand increases to 790-1180 cubic meters.Irrigation significantly increased the water consumption of hemp, but the water consumption coefficient decreased with the increase of hemp fiber yield and seed yield.Mineral and organic nutrients can effectively increase fiber yield and quality under irrigation conditions.All these indicate that irrigation and nutrition are causation and promotion of each other.