Part 5: Cultivation methods


How to grow herbs ?

Annual herbs such as dill, caraway, basil, borage, chamomile, garden marjoram, chervil, cumin, parsley, anise, coriander, and annual bean herb are sown. This is done in spring from late March, on site, in the soil. Also, frost-sensitive annual herbs such as basil are sown in March-April, under glass. Seeds that germinate slowly (parsley) too is better sown under glass.

Everlasting herbs such as thyme, chives, sage, oregano, remaining savory, tarragon, hyssop, lovage, Catholic chervil, Galium odoratum, garden burnet, fennel, garden sorrel, lemon grass, mint and horseradish are propagated by sowing, divisioning, cutting, air/soil layering or by planting bulb or tuber. This propogation is done directly in full soil. However, the cutting of eg tarragon is best done in a greenhouse because the cuttings are then in a growth-promoting climate and will also dry-out less.

Herbs are not only supplied and used in their natural growingperiod. The cultivation of herbs can also continue during the winter months. The cultivation during the winter months is then completely done in a greenhouse.

According to the location of cultivation, we can make the following division: A. Outdoor

  • In full soil
  • In container

B. Sheltered

  • In full soil
  • In container
  • In pot or press pot
  • In trays or multi plates

Cultivation method in full soil

  • Tillage
    • The goal:

getting a good sowing or planting bed. By loosening the soil and then pressing it, we obtain a good air/water ratio. Simultaneously we dig under organic fertilization. A good tillage is the basis for a good crop growth. Plants that are root well also have a good growth.

    • Classification of tillage operations:
      • Main soil manipulation:

This has as a purpose to loosen the soil deep enough, as required for the plant to grow. Simultaneously, organic matter is dug under.

        • Plowing:

The soil is cut, broken and reversed. After the plowing, additional operations are still required. A normal plowing depth is 25 cm. For heavy soils, this is a good manipulation that is best done before winter so that the soil can freeze out and is then much crumbleable in spring.

Newly-found farm experiments show that much nutrients evaporate and leak out of the soil if it is plowed. Suggestion claims that it is unneccessary and if alternative methods is used to control weeds, the yield can be larger without plowing. (I can only find information about this in swedish)(here is one googletranslated article)[1]

Results: less amounts of diesel used, soil retains more water, nitrogen and carbon. Less eutrophication of waterways around the farm.

        • Digging out:

When digging out (manual or machinal), each soil block is dropped separately. This creates an extremely open structure. Here again finishing manipulation steps are needed.

        • Digging out-milling:

This is an intermediate form of digging out and milling. With this step, the soil is put sowing or planting-ready in one single operation. Because the soil is usually somewhat too loose, this manipulation is often done when the planting is imminent.

      • Putting sowing or planting ready:
        • Milling:

This is a very superficial treatment in which the soil is crumbled very finely. This should be applied just before sowing or planting. There is a threat on somewhat more heavier soils of soil consolidation after a rain.

        • Cultivating:

These are tools that rake thesoil, and while doing so, brake the large soil clods and crumble them. Simultaneously, the crumbled soil is pressed. Several tools such as the vibrating teeth cultivator and the rotorharrow are used. This manipulation generates an ideal sowing bed.

        • Harrowing:

A harrow has fine, shallow teeth that loosen the upper part of the soil and cut them.

        • Rolls:

Simultanuously with putting the soil sowing ready, the soil is rolled to attain a adequatly consolidated sowing bed. When planting, the sowing bed needs to be less pressed.

      • Maintenance operations:
        • Shoveling:

Here, we loosen the upper centimeters of the soil with a a hoe or a hoe machine. The purpose of hoeing is to aerate the soil, allowing oxygen to reach the roots (after a heavy rain) and allowing the soil to dry out less quick. It is also the ideal way to mechanically remove the weeds. The weeds are cut just below the ground surface.

Under wet soil conditions, the soil can not be tilled regarding to possible deterioration of soil structure.

Sowing

The sowing in full soil is done from late March. With this on site-sowing, the sowed plants are not transplanted. They are later thinned-out at the desired spacing. The sowing can be done scatted or in lines. We prefer to sow in lines because the weeding can then be done with a hoe or hoe machine.

Sowing by hand done in sowing trenches that are drawn near the sowing line. For this, we use the handle of a rake or the blade of a hoe. The depth of the sowing trench is related to:

  • The size of the seeds. The smaller, the shallower.
  • The expected weather, with rainy weather shallower, deeper with dry weather.
  • The germination period, seeds with a long germination period are sowed deeper.

Take care to not to sow with a too small spacing, the plants will then quickly compete with each other making them weaker and too lenghty. Divide the seeds on equally spaced distances.

After sowing, the sowing trench is gently filled by raking the soil over it, and slightly pressing it, so that the seeds make good contact with the soil. With light-based germers, the seed is pressed but little or not covered.

After the sowing, depending on the moisture content of the soil, it is watered. This is done with a fine spraying to avoid the consolidating of the soil. Often we will, to avoid the hardening of the soil, need to keep the soil moist, until the germs emergence.

With seeds that have a long germination period (3-4 weeks), the seeds can be inbibited. The seeds are allowed to swell up to 24 hours in water and are then layed out in a box with damp toilet paper, covered with a glass or foil. From the moment the seeds begin to germinate, we carefully sow them.

Plants

Plants cultivated in pots, press pots or sowing boxes have large root systems. For this, the planting holes are best made with a spade. Make the holes large enough for the roots and plant as deep as the pot or even somewhat deeper. Divisioned plants such as chives, mint or the rooted shoots of thyme are planted with bare root in the soil. We use for this a planting stick or planting shovel. Thyme, and mint are planted deep enough so that the bare stems are below the soil and roots too can be formed there. After the planting, the plants are repeatedly watered at regular intervals until the plants are well in growth.

Sheltered nursing

Nursering from seed

Sowing plot For a good emergence of the sown seeds, a good sowing soil is needed. On such a sowing soil, we place the following requirements:

  • it must be able to hold enough air
  • it must be airy
  • it must be as fine as possible so that the seed can be dispersed finely and a so that there is a good contact with the soil in order to germinate
  • it must be disease free
  • it must be nutrient-poor

Sowing soil is usually a mixture of tuinmolm, peat and sand. In the shop, good sowing soil can be purchased.


Place of sowing - not on site This means that the plants are to be moved one or more times. Possibilities are: A. Sowing in containers As a seed box, we take styrofoam boxes with a 6-8 cm depth. We fill the box halfway with sowing soil and we gently press the edges with a board. The remaining soil is now sifted into the box unto 2 cm below the edge, and the edge is gently pushed, this causes them to dry out less quickly. The soil surface needs to be made smooth pressing it. The seeds should be equally distributed over the entire box. Seeds that gather up into a pile are too close to each other and have more chance of fungal attack. The finer the seed, the closer they can be together and the larger the seed, the farther apart. The seed is divide into 2 portions. We sown with the bag or with a folded paper. We place the forefinger inside the folded piece of paper and hold it down with thumb and middle finger. Sprinkle in a reciprocating motion, as smooth and as thin as possible, into the seed box. Turn the box sideways and repeat with the other portion of the seeds. Very fine seeds is best mixed with dry silver sand for better dispersal. We introduce a covering layer (sowing soil mixed with sharp sand) with a the thickness equal to the seed. The newly sown boxes are watered with a fine spraying. In order to prevent the moisture needed for the germination of evaporating, the box will be covered with a glass or put under plastic. Trough the evaporation, drops will hang from the glass that will fall on the soil, possibly causing fungi to spawn. Therefore, the glass plate will be turned if too many drops adhere to it. In the beginning, we place a newspaper over the glass. Most plants are dark germinators. The newspaper prevents the young seedlings of burning by the sun. Once the plants have germinated, we remove the glass plate.

B. In flower pots or press pots If plants are inmediatelly sown in flower pots or press pots, the cultivation takes less time. In the beginning however, you need more room. On can introduce the seeds in several ways:

  • By laying out coarse seeds
  • By driving fine seed with a nail into the soil, there are then several seeds per pot

Professional cultivators grow many herbs in pots. So as to be able to keep the plants in a pot a long time, nutrients need to be administered (sowing soil=nutrient poor). These are usually given along with the water.

C. Sowing in trays or multi plates This are polystyrene plates that are divided into a large number of boxes or cells. In each box, a seed is introduced. The sowing is done mechanically. Each plant is grown individually and thus forms a plant ball, hence the name balled plants. Advantages are:

  • Diseases can difficultly spread
  • The transplanting of the plants is 2X as fast
  • No transplanting shock since no root fracturing occurs

After the sowing, they are placed in germinating cells where there is an optimum relative humidity and temperatures.

Transplanting This is the transplanting of the young plants from a seed box, at the time when they are still small and have little roots. Transplanting can be done in:

  • Boxes
  • Press pots or flower pots
  • Open-field (full soil)

Some plants are already transplanted in the germ leaf stage, others are transplanted with the inset of the 1st or 2nd true leaf. When transplanting in boxes, we fill a box similar to sowing. The young plants are taken out of the seed box by lifting the plants with a small transplanting board. We start in a corner of the seed box. Pick up the plant by placing the leaf (without touching the stem) between thumb and forefinger of one hand. We make a hole with the transplanting board, and the plant is placed sufficienctly deep (up to the leaf) in the hole. We start transplanting from the middle of the box and work the row from left to right. We then rotate the box and finish the rest.

When transplanting in press pots, the plants are placed in the center of the cleared space. Make sure that the roots wind up in the hole of press pot. With the fingers of the other hand we gently press from the outside inwards. Press pots have the disadvantage that they easily dry out and harden making them difficultly rootable and slowing down the growth.

When transplanting into pots, we scoop the jar full with soil and make a hole in the center of the soil in the pot with the finger. We place the plant inside the hole and press the soil with thumbs and forefingers. The transplanted plants are watered to prevent wilting. After the transplanting, the plants are not put in full sun so that they can quickly start to grow.

Nursering of clones

A new plant is formed from large or small parts of the parent plant.

Divisioning With this, the plant is divisioned into several pieces. It is important that:

  • Each piece contains at least 1 eye
  • Each part has enough roots
  • Each part contains sufficient food reserves

When divisioning, we follow these steps: The mother plants are uprooted and the excess soil is shaked off. The excess in leaves is removed. Make sure that growing points, shoots and roots are not damaged. Hold the plant with both hands, the thumbs as close as possible to the breaking point. Breaking causes less damage than cutting trough. If breaking is not possible, the woody or fleshy part is prepared with a knife or scissors, never cut trough the roots. Torn plant parts are never allowed dry out. As soon as possible plant it out in a pot of in the open-field so as to ensure a smooth regrowth in sufficiently nutrient-rich soil. Water the plants. In sunny weather we cover the plants to fight dehydration. Among others, used with chives, lemon balm, tarragon, lovage, oregano, sage, thyme, fennel.

Stolons Stolons are vegetative shoots without food reserve that grow in the horizontal plane beneath the soil surface. Stolons will produce in their knots roots and erecting stems. A new plant is made if the connection is broken with the mother plant. The young plants that already have some roots are cut from the parent plant and are planted in open-field or in a pot. It then grows to a full plant. Is, amongst others, applied with mint.

Ground and air layering This method can be applied with thyme. With ground layering, an adult branch is deflected to the soil and is fixed with a clamp or a bracket. At the spot where the plant touches the soil, it is covered with a layer of soil. The branch's head will be placed slightly above the soil surface. After the branch has made underground roots, it can be cut from the mother plant. This young plant can then be transplanted. With the air layering, we cover the heart of the plant with a layer of soil. Once the branches have made roots, they can be cut from the mother plant. Ground and air layering happens in spring, where the rooted plant can be cut in summer.

Cuttings When taking cuttings, we take a part of the plant without the roots and allow it to root in the soil or in a substrate. When taking cuttings from herbs, we usually take a shoot cutting with a heel (heel cutting). We rip off a young side shoot from an older branch so that a thin slice of wood with bark (the heel) also comes along. This piece contains cambium or divisioning tissue that provides a smooth rooting. The point of the heel is cut and the leaves near to it are removed. The bottom of the cutting is then dipped 1 cm deep in growth hormone and the excess liquid is removed (optional !). The plant contains several natural growth hormones. The plant hormone auxin is formed in the young green plant parts and is transported downwards. On his way down, auxin inhibits the growing of eyes (side shoots). In plants without roots an accumulation is created at the wound surface. This accumulation promotes the formation of callus and roots (auxin promotes cell divisioning). With some plants that root difficultly, a shortage of this plant hormone occurs. They succeeded in making this plant hormone chemically. Brand names of these chemical growth hormones are Rhizopon, Aglukon, Stimroot.

Then the cutting is placed into cutting soil as soon as possible in order to allow rooting. This can be in a cuttings box, a pot or multi-plates in which 1 cutting is placed per cell. The cutting should not be placed to deep, only the portion of the cutting that is free of leaves. The air humidity needs to be sufficiently high enough when cutting. The plant can evaporate, but does not yet have roots to absorb moisture. To counteract evaporation, the cuttings boxes or cutting plates are placed under plastic film. The cuttings are lightly moistened after the placement and are placed under a plastic foil. When the air humidity is too low, the cuttings will start to hang over. When there is much water in the air, then the cutting does not have the tendency to evaporate water. At professional companies, the cuttings are placed under water mist. With a rain pipe, a water mist is made that applies a thin layer of water over the leaves. The cutting can not evaporate. Between the cuttings, there is an electric sensor that, when the humidity is below 95%, causes the water line to start spraying. Light and heat promote the rooting of the cuttings. The temperature in the seed box is best 2-5°C above normal cultivation temperature (17-20°C). We will have to cover the plants from the sun during periods of high solar intensity. The temperature would otherwise rise too high. After the cutting has rooted enough, we will plant it outside or in a pot after hardening off.

Potting Potting is placing a well rooted plant in a pot. This can be cuttings that have sufficiently rooted, divisioned plants, ... The potting soil that we use here must contain sufficient nutrients. When potting plants that have few roots, we proceed similar to transplanting into a pot. When potting plants with a good root wig, we work as follows: We take the pot in one hand and hold him with 2 fingers. We hereby scoop soil into the pot. With the hand, we press the soil that is present in the pot to the back. After this, we take a plant and keep it at the right height inside the pot, the roots are held on the side of the pressed soil. With the other hand, we fill the pot with potting soil. Then, we press the soil with both thumbs. The pressing of the soil is important. The more we compress the soil, the slower the growth. The plant will then be stronger, but the growth is slowed. Try to minimize the damaging of roots when hoarding. The less damage, the faster the plant will grow.

Climate with sheltered nursering

Light

Why light? Light is the most important growth factor, as an energy source to connect the carbon dioxide from the air and the water from the soil to carbohydrates. Light means plant activity = evaporation. Light dependant ! Light is thus the limiting factor in growth. Especially in periods of low light, this must be taken into account. Low light with high temperatures in the greenhouse gives elongated, weak plants. In the winter months, we will thus regulate the temperature depending on the light.

  • With sunny days, we turn the temperature up
  • With dark days, we turn the temperature down

To get an optimal light entry in the low-light winter months, we will make sure the glass is clean (glass is washed at interior and exterior, dirty glass can give up to 30% light loss). In winter; to use the little light of the wintersun, the greenhouse is best oriented with the long axis from east to west. In winter, the arc between the points of rising and falling is 60 meters, and 120 meters in summer. In winter, only the south of greenhouse gets direct sunlight. In the summer, the ends also get sunlight in mornings and evenings.

Temperature

Because of the greenhouse effect, the temperature in the greenhouse will increase with sufficient light radiation. Light reaches the Earth as short-wave radiation, which easily penetrates glass and plastic film. These rays heat everything they touch, such as soil, plants, pots, tablets, ... These will redirect a part of that heat back as long waves. Because glass blocks these long waves, the result is a large increase in heat in the greenhouse. When radiation passes through plastic fil, it is diffuse and the reflected long-wave rays are not blocked by the foil. Plastic greenhouse's thus also cool down a lot faster than glass greenhouses. Direct sunlight must be able to hit the glass at an angle of 90 m, if the maximum amount of sunlight needs to be entered. If the angle is greater or smaller, a part of the sunlight will be reflected. The sunlight reaches the earth in winter at an angle of about 15 m. At dark days, this means little light and therefore low temperatures. At sunny days, this means higher temperatures.

With cold greenhouses (unheated), the temperature will have great fluctuations in spring. With frost, the greenhouse temperature will fall below the point of freezing. To prevent damage to the crop, we can additionally cover the plants with foil or fleece. A cold greenhouse or a cold tunnel greenhouse is then used for the winter cultivation of energy-poor leafy crops, for taking cuttings in spring and autumn, for a cold cultivation, to hibernate sensitive plants in winter. With hot greenhouses we will, by means of a heating element, be able to control the temperature in the greenhouse and thus prevent large fluctuations. For this, we make use of tube heatening (heater circuit with circulation pump and piping in the greenhouse) or a CO2-burner. Depending on the crop, we will make use of:

  • Soil heating: applied with container beds and seed beds
  • Tablet heating: applied with seed and cuttings tablets
  • Space heating

Depending on the crop, a minimum night and a minimum daytime temperature are set. The heating is always done with closed windows or a closed ventilation system in order to prevent energy loss. Heating has an impact, not only on the temperature, but also on the RH (relative humidity). The warmer, the more water vapor the air can contain. With a temperature increase, the RH will decrease the. This is a technique often used in dry firing.

Ventilating

Why ventilate ?:

  • Because of the temperature regulation: Taking into account the amount of available light, every crop has a maximum temperature. Above this temperature the plant will exhibit negative symptoms. When these is exhibited, the greenhouse will need to be ventilation.
  • To refresh the air: The carbon dioxide content must be maintained. In a closed-off greenhouse, this is impossible. The composition of the air is 78% nitrogen gas, 21% oxygen gas and 1% other gases of which 0.03% CO2. Given that plant consumes, with a strong activity, allot of CO2, a shortage will soon emerge that prevents growth. Professional cultivators are will increase the CO2 concentration heavily with a strong solar radiation in order to speed up the assimilation (eg in leafy vegetables). This can be through the use of CO2 -burners.
  • For the regulation the air humidity. The amount of water vapor that the air contains varies between 2 and 30 gram/m³. When the air contains too much water vapor, this will prevent the evaporation of the plant promote the occurring of diseases. By ventilating, a part of the water vapor leaves the greenhouse, together with the hot air. A good relative humidity is RH = 70%.
  • To harden off the plants. Plants that are nursed sheltered and are then planted outside should first be prepared on the outside conditions before that they are planted there.

How to ventilate ?:

  • Trough the roof: warm air rises. 1 m³ of dry air of 0°C and with a pressure of 1 bar weighs about 1,300 grams. If this air is heated to 30°C, the air expands. 1 m³ of this air weighs only 1180 grams, or 120 grams less. This causes convection currents, the warm air cools at the greenhouse roof, falls back down and the hot air rises.
  • The side sheltered from the wind: This is the side of the greenhouse opposing the wind. Beware of east winds (dries too much).

When to ventilate ?:

  • at daytime: depending on the temperature and the amount of light in winter at a sunny day, the temperature in the greenhouse can be higher, the windows are then kept closed in the morning, so that the temperature will rise due to the greenhouse effect. With a cloudy day, the temperature should not be so high in the greenhouse, and more ventilating can be done.
  • in the evening: after a sunny spring day, the windows will be closed earlier so that the greenhouse can not cool off too strongly and so that the night-day temperatures do not differ too much. After a cloudy day, the windows will be closed late or even not at all. The plant then comes more quickly to rest.
  • in the morning: avoid sudden temperature changes

Shuttering

Why shuttering ?:

  • As a sun covering to reduce the temperature when ventilating is not sufficient.
  • For protect seedlings, transplants and recently cut plants from drying out and to promote regrowth.
  • To slow down the quickly increasing evaporation with sudden weather transitions from a dark period to a sunny period in spring.
  • In winter as an energy conservation (energy shutter)

Sun shutters: In a non-shuttered greenhouse, the leaf temperature is up to 15°C higher than the air temperature. If the leaf temperature gets too high, the leaf will be burned. A shutter reduces the radiation and thus the leaf temperature to a few degrees above the air temperature. The air temperature can be kept, trough a a good shuttering and ventilation, to a few degrees above the air temperature. Too dense shutters (films), can inhibit the evaporation of the plant, which has a slowing effect on the leaf cooling and the leaf temperature rises again possibly causing the plant to be burned.

How to shutter:

  • Persistent: chalk, chalk white. The more is dissolved per liter of water, the denser the shutter. Apply using a brush, smear or sprinkle. Calcium shutters halve the sun intensity. In dark summer days, this has large drawbacks. These shutters are removed in autumn.
  • Temporary shutters: shutter cloths made of:
    • Fiber (polyester) and acrylic cloth (not vapor-tight)
    • Foils (vapor-tight)

These shutters are movable in the greenhouse and can be pulled open and closed as needed. Eg in the form of a:

  • Slidable shutter
  • Rollable shutter
  • Foldable shutter

Watering

Why watering ?:

  • Water is a means of transport, temperature regulation, nutrient (needed for sugar formation) and it also keeps the plant firmly upright.
  • For the soil, water is necessary as a temperature regulator and to maintain the soil structure (too much can damage it)
  • For the fertilizer substances in order to dissolve

How to water ?:

  • Spraying: on seed beds, cutting beds, ... with a fine sprayer
  • By watering can: Rose pointed upwards, heaviest water impact next to the seedbed
  • By garden hose: fine drop, water in a big arc so that it warms up and lands gently.
  • By rain pipe: PVC pipes that are suspended at the roof of the greenhouse. 1 pipe per 3,20 caps, spraying caps at 1.5 meters.

As a spray head, we use ricochet caps:

  • bar cap
  • sphere cap

The caps are pointed upwards, but so that they do not spray the walls or roof.

When to water ?:

  • Always in the morning so that the plants are dried up at night.
  • In sunny and drying weather, th plants than require the moisture and have a chance to dry. A wet plant that can not dry up also can not evaporate, so that there is no supply from the roots and thus no growth. A plant that is left wet too long is also an ideal target for a fungal attack.
  • With very hot weather, watering is done in the evening
  • Avoid giving the plants get a cold watering and that the crumb structure of the soil gets damaged.

How much water ?: This is depending on the crop type, weather, crop size, soil type, season. In winter, we give water in short shifts to leafy vegetables to not too wetten the plant and soil too much. A few minutes, every few days, depending on the weather. In summer, we give gifts of 5-10 minutes. A light soil color means water shortage. Soil of 10-20 cm deep is squeezed and dropped using one hand: it should not fall apart, otherwise it is too dry. A plant with a bright color and less shiny leaves that also falls over at night requires water.

Flushing: In greenhouses where there is no natural precipitation, the upper soil layer will salinate trough the use of organic and chemical fertilizers. After all, we give just enough water for the plant and soil water will rise further causing salts to get stuck in the upper layer. Therefore, after a summer cultivation, the soil in the greenhouse will always be need to be flushed. This is done by watering in shifts of 15-30 minutes, separated by an equally large break, and this for several hours. The present salts are then washed out downwards and discharged trough the drainage pipe.


Gathering, harvesting, drying and storing herbs

Gathering herbs

  • Period of gathering

The summer is the best time for harvesting for most herbs. If one only wants young leaves (eg stinging nettle), then one can best pick these in spring when the plant is still full of energy or in late summer when it has a second growth period. Roots and rhizomes are best collected in the fall or in early spring. They then contain the winter reserves of the plant. Bark of young branches and trunks are best removed in late summer when the bark easily detaches.

  • Time of harvesting
    • Leaves

Green kitchen herbs are generally picked before blooming, when the leaves and leaf stems are still soft (eg cress, nasturtium, borage, burnet, tarragon, ...). For herbs that need to be rendered storable, the best period of harvesting is right before the blooming. The plants then have the most leaves and the highest levels of active substances, especially with plants that contain etheric oils. Pick leaves on a dry and sunny day, early in the morning when the dew has evaporated from the leaves. Herbs contain the the least amount of water in the morning. Do not gather the herbs if they are humid by the rain. Leafs of with the aroma is of importance (rosemary, sage, lemon balm, ...) are best picked around noon, when they contain the largest amount of etheric oils. Do not pick them too late in the day because due to the heat the volatile etheric oils evaporate.

    • Flowers

Flowers can be harvested during the peak of the bloom, just before or immediately after the flower has fully opened. Also pick the flowers in the morning, when the dew has evaporated from the flowers, but when the plants have not yet been dried out by the sun.

    • Seeds

Pick the seeds in the late afternoon or in early evening, when the plant is as dry as possible. For plants whose seeds easily fall out of the seed casings, it is best to harvest in the morning.

  • Method of harvesting:

Harvest with a sharp knife so that the plant is not damaged. Young plant parts can also be picked. Avoid any possible bruising of the leaves. Remove damaged and brown leaves or flowers. When collecting seeds, we pick the entire stem and optionally bind a paper bag around the seed casings. Select plant parts that are free of animal droppings, are not eaten by insects, and appear fresh.

Conserving herbs

  • Drying
    • Preparation:

Leaves: Remove the lower leaves and hard leaf stems, remove dirt and insects with a moist cloth or sponge and pat it dry. Never wash the herbs, this slows down drying. Roots: The roots are dug out in their entirety and the loose soil is shaken off. The roots are then washed under cold water and patted dry. Do not peel the root, important components are otherwise lost. Bark: Bark may need to be washed to remove moss and insects.

    • Drying method

Herbs contain more than 70% water. The trick is to get the water from the herbs in a quick manner, so that the oils are preserved. The drying of herbs can not be done in the sun, because this is too hot. Herbs should be dried quickly, but not at temperatures above 35°C. Dry the herbs on a dry, dark, well ventilated place at temperatures between 20-30°C. Dark, as trough too light, the colors deteriorate, and well ventilated because excess moisture should be drained.

One can tie up the herbs in loose bunches and hang them up upside down on dry walls or lines. The drying of seeds is done by hanging them up upside down on the stem with a paper bag wrapped around the seed casings so that these fall into the bottom of the bag. For delicate flowers and leaves, special drying floors can be used. A drying floor is made by stretching coarse linen between a wooden frame. Wire mesh can also be used for this. Make sure that between there is a minimum space between the grids of 15 cm. The best results are achieved when these are used in special drying closets at a certain temperature. The flowers or herbs are sprinkled 1 layer thick. Roots and bark can also be hung to dry above drying floors. It is hereby good to dry the material daily. After 4 to 14 days, the herbs should be dry. Leaves are dry if they are brittle. Petals should feel dry and be slightly brittle.

    • Storage

Strip the leaves from the stems and crumble them. However, do not make the leaves too fine. Rosemary, sage and thyme are not stripped and stored as stems. Dried bay leaves are also best kept in their entirety. Storage is done in an airtight container.

Seeds and flowers are stored in an airtight glass jar after drying. Herbs van not be aduquatly stored in plastic or paper objects. Paper absorbs etheric oils and plastic may promote the formation of molds. If there's moisture on the inside of the jar, it means that the herbs were not properly dry. Remove them from the glass jar and let them dry on paper.

    • Shelf life of dried herbs

Most herbs have a shelf life of about 1 year. Basil, lovage, mint and marjoram are longer storable. Lemon balm, parsley, savory, tarragon and can store approximately 9 months. It is best to refresh all herbs every year.

      • Freezing

Some herbs lose their flavor when dried. It is best to use the herbs fresh. Freezing is also a good method. Wash the herbs carefully. Then they are shaken when dry. Herbs can be stored frozen if they are used within 2 months. For a long period, bushes are made of them that are then dipped in boiling water for 1 minute and then in cold water to bleach them (blanching). They are frozen in sealed plastic bags for a longer period (up to 6 months). Herbs that can be frozen are: basil, chives, dill, parsley, chervil, marjoram, mint, fennel, sorrel, tarragon, thyme

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