Hydroponics BC

Tips to Increase Propagation Success

Many customers request information about how to increase their propagation success rate. Successful propagation is, in essence, simplicity, however there are some guidelines that when followed, can dramatically improve the ultimate success rate. These are listed below. Please feel free to ask any of our staff for more information, they would also be pleased to give you a simple demonstration if necessary.

Sterile Conditions & Equipment

Before attempting to germinate seeds or propagate cuttings, have all necessary equipment ready. Make certain that tools, equipment and trays are sterile. Scalpels, secateurs, or scissors should be razor sharp. If a previous crop was infected with disease, this is even more crucial. The entire growing environment should be thoroughly cleaned with a bleach solution and this process should include all equipment that will come into contact with the new seedlings.

Suitable Propagation Medias

Preparation of Growing Media

Correct preparation of the growing media chosen can markedly improve the ultimate success rate.

Rockwool Propagation Blocks

Rockwool propagation blocks should be rinsed with a 1/2 strength nutrient solution to which has been added 4 drops of pH lower solution for each 2 litres of nutrient. Allow the blocks to soak in this solution overnight if possible then discard the solution and just prior to sowing seeds, rinse the propagation blocks with 4 litres of 1/2 strength warmed nutrient solution to which has been added 4 drops of Rootzone Accelerant and 5 Drops of Superthrive. Before planting ensure that the blocks have drained completely. Rockwool should be moist but not wet and should never be allowed to sit in pool of nutrient/water. If the blocks are dripping they are too wet.

Jiffy Pots

Jiffy pots are compressed peat pellets that expand when soaked in water. Before use they should be soaked on a 1/2 Strength nutrient solution to which Superthrive and Rootzone Accelerant have been added. It is important to remember to closely follow the directions for use on the labels of these products to avoid burning the new shoots once the seeds germinate. Once the pellets have expanded they should be removed from the soaking solution and allowed to freely drain, after which seeds can be sown.

Perlite/Vermiculite Seed Raising Mix

Perlite /Vermiculite seed raising mix consists of 50% Perlite and 50% Vermiculite. This should be thoroughly mixed and wetted with a 1/2 strength nutrient solution to which Superthrive has been added. Allow this mix to drain freely and then sow the seeds just below the surface of the growing media.


pH is important not just for established plants but also when propagating. Always maintain pH levels between 6.2 - 6.8 pH. pH levels should be tested and adjusted if necessary before sowing seeds and at least weekly throughout the growth of the plant. Incorrect pH levels can cause toxicities of some nutrient elements and cause other nutrient elements to be unavailable to the plants therefore adversely affecting plant growth.

Temperature & Humidity

Maintaining constant temperature of between 20 - 28C encourages rapid germination and healthy seedlings. It is important to note that the faster clones or seedlings establish, the higher the success rate and the healthier the young plants will be. Temperature and humidity play an important role in successful propagation. Clones or seeds should be placed in a cloning chamber to promote a warm, moist environment. While humidity is important, monitor the chamber daily to avoid excessive condensation build up. As a rule, if water droplets trickle down the sides of the chamber, it is too wet and the vents should be opened, as extremes of temperature and/or excessive humidity will inhibit germination and the establishment of healthy seedlings.


For propagation purposes, fluorescent light is ideal operated for between 16 - 18 hour per day. The light should be operated on using an electronic timeswitch to ensure that the ON time and OFF time are the same each day. As fluorescent lights are of a low intensity they should be positioned as close to the plants as possible.


Seedlings and clones need only a light mist spray to keep media moist and raise humidity, and provide food for the young plant. When misting, it is best to use a warmed 1/2 strength nutrient & Superthrive to avoid burning the tender young shoots.

CLONING- Step by step Introduction

Cloning involves preparing a small cutting taken from a mother plant, treating the cut stem with a rooting hormone and placing the prepared stem cutting in a cloning chamber. The clone should grow roots and become an independent plantlet exhibiting identical characteristics to its' mother plant. Most soft or semi-hardwood cuttings will have developed roots within a week to ten days.

The most successful method of growing clones is in the Growool Propagation Blocks. Using this material ensures a high rate of success, ease of use, short number of days to root development and a fairly stress free clone. Also try CLONING KITS which contains all the necessary items to begin successful cloning.

The name cloning simply stated means taking a cutting from a mature female plant in the vegetative stage and inducing it to grow roots. Clones will replicate the mother plant in every way ie: size, sex, colour, smell, taste etc. It is therefore crucial to have a mother plant of outstanding quality. The newly rooted cutting can be induced to flower immediately, or it can be put under a vegetative light cycle to attain a larger size.

As soon as the clone is large enough you can begin to take cuttings from it. Contrary to rumour, this can be done infinitely without any loss of desired qualities.

The Mother Plant

It is important to choose a mother plant carefully. When selecting a suitable mother plant consider the following:

It is important to remember that your mother plant should be healthy and stress free. Cuttings coming from a stressed mother plant may root poorly, be slow growing, produce poorly and become mutated. It is important to reinforce that the condition of your mother plant is paramount to the success of your clones. Vigorous genetic stock can be lost by cloning from poorly cared for mother plants. As a general guide do not take more than 20 - 30 % of the vegetative material from each mother plant and do not take cuttings from the mother plant more than three times.

Each time you take cuttings it is a good idea to start a new mother plant from the most vigorous clones. Remember if growing initially from seed to select only the best genetic plants to use as mothers for cloning. Seeds will never produce the same consistent results you can expect from clones.

Cloning - The Cloning Kit.

How To Take Cuttings

Before you begin to take cuttings, it is a good idea to have all the equipment ready and in good working order. All equipment should be thoroughly cleaned and the cloning area should be as sterile as possible.

Step 1.

Rinse the propagation blocks with a half strength nutrient solution to which has been added 4 drops of pH lower per two litres. Let propagation blocks soak for up to 10 hours prior to cloning in this solution. Discard soaking solution and just prior to cloning rinse blocks again with 4 litres of half strength warmed nutrient solution to which has been added 4 drops of Rootzone Accelerant and 5 drops of Superthrive. Insert thermometer into cubes and allow temperature to reach the green zone before cloning commences. Temperature should be maintained day and night within the range of 20 to 30 Cent if cloning is to be successful.

Step 2.

Select cuttings - cuttings can be taken from anywhere on the mother plant provided the stem is of the correct thickness. Stem thickness should be between 4mm to 6mm diameter. Take cuttings with about four sets of well developed leaves and approx 100mm to 150mm in length. The topmost growing shoots make excellent cuttings however make sure the wood is of the correct thickness and not too green or to woody. You may wish to take a number of cuttings at one time immerse them in an ice cream container, or similar, filled with tepid water to which you have added a few drops of superthrive anti-stress formula.

Step 3.

Take the single edged razor blade and begin trimming your cuttings. Take cuttings one at a time from tepid water and now trim bottom two sets of leaves flush with stem. Trim approx 50% of leaves by cutting across the leaf surface. It is hard for the cutting to keep these large leaves alive and they usually wilt and fall off if not cut in half. Cut the stem at fourty five degrees across the bottom leaf nodes. Gently scrape the cut area around the bottom of the stem. This disrupts the cells on the stem surface and helps them change into root cells. Take whatever rooting hormone you have purchased and dip the bottom of stem into your rooting compound. Here is a tip: Do not dip directly into rooting hormone bottle instead pour some off into a small container such as a thimble and discard what is not used. This saves you introducing any bacteria or disease into main container. Store main bottle of rooting hormone if refrigerator after opening.

Step 4.

Now you are ready to put the cuttings into the growool propagation blocks. Gently insert the stem into the cube making sure the stem does not protrude out of the bottom of the cube. After all the clones have been prepared and placed in the propagation blocks you may water the block again with half strength nutrient solution to which you have added Superthrive and Root Zone Accelerant. Water the blocks until nutrient freely runs from the blocks allow to drain for a few minutes then place blocks inside the cloning chamber and place the chamber over the heating pad. You should close the vents on the grow top for the first 3 days. Check moisture and temperature for the first couple of days and mist cuttings morning and night with water to which you have added a couple of drops of Superthrive. Be careful to ensure that you do not have water sitting in bottom of tray. Growool cubes should be able to freely drain at all times. Place cloning chamber under flourescent fixture for approx 16 - 18 hours per day.

Step 5.

After three days open the vent on the Grow Top. Monitor progress of clones for another 4 to 5 days by this stage it should be time to take Grow Top off the unit and expose clones to normal air - still continue misting morning and evening. Again monitor nutrient and moisture levels in the propagation block. By the end of a further 5 to 8 days you should be able to see root hairs protruding from the propagation blocks. Healthy roots look thick, white and hairy. Sickly roots look thin, yellowish or brown and hairless. The clones with the healthiest roots will be the same ones you will be proud of at harvest time.

Step 6.

When your cuttings are well rooted and have begun to shoot it is time to transplant them into you growing system. Slowly introduce them to full strength nutrient and place them under a H.I.D. light system. Remember the new clones are tender and exposing them rapidly to a full strength H.I.D. lamp after the fluros would be a shock. Care should be taken to acclimatise your new clones to the brighter light. Start by raising the H.I.D. lamp approx one metre above the clones for the first few days slowly lower the lamp over the next week till the lamp is at the correct height. This will ensure a smooth stress free transition to growing under H.I.D. lamps.

General Tips

When setting up and maintaining your cloning box you must take care to provide your clones with the best propagating environment and care possible. To ensure fast rooting and high success rates, high humidity, 16 - 18 hours fluorescent light, proper air circulation, strict attention to cleanliness and correct bottom heat are absolutely necessary.

Humidity should be 80-85%. If air in cloning room is dry mist more often. Black leaf edges, black spots on leaves and mushy stems (damping off disease) are all indications of too much moisture and poor airflow. It is also essential that you provide adequate bottom heat. Do not try to skimp here. The cuttings and their cubes should be warm 24hrs per day. Often people fail to clone successfully because they do not provide bottom heat and clones will root poorly when nightime temperatures dip under twenty degrees centigrade.

Remember: Stress is bad. The faster your cuttings develop roots, the less stress they will undergoe. Any stress the cuttings are exposed to can result in a decrease of final yield by up to 50%. So treat your cuttings with a lot of T. L. C.

In emergencies: If you have to take cuttings from blooming plants, cut all the flowers off the cuttings. This will reduce stress. If planting clones outdoors treat with care and slowly acclimatise to the sunlight. Clean trays thoroughly between cycles. Use a weak bleach solution and water. Lots of bacteria and fungii spores can grow in dirty wet trays. This will lead to damping off disease. Remember cleanliness is very important. Do not resue growool cubes after they have been used throw them out and buy fresh ones they are inexpensive easy to store if kept dry. Do not clone from mother plants infested by spider mite. Keep your mother plant free of spider mites. Your cuttings will have little or no resistance to spider mites and will stress badly if attacked by the mites during cloning.

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