Growing Tips & Techniques

Plant growth is a very natural thing. We must respect nature, however, we will always continue to try to extend the borders and explore new ways to improve quality, production and growth control. This is also why every grower has their own specific techniques. We have provided some standard techniques here, which have proved themselves over time.

Positioning & Moistening the Substrate

Maximize the substrates potential volume by following these simple startup tips.

The ground under the slabs must be on a flat surface with a slight slope. This allows the slab to drain quickly and easily. The slabs are designed to be fully drained.

To create the optimum air-water ratio during growth, it is essential to initially soak new substrates in a proper nutrient solution. If the substrate is not completely saturated to begin with, you are not maximizing its soil potential volume. 

It is recommended to soak Speedgrow cubes, plugs and slabs in water with a pH of approximately 5.5 plus a nutrient solution. Use a pH down solution and a fertilizer designed for the crops you’re growing.

For additional information about water retention rates see the Research Page

Speedgrow Green Slab in Use

Drainage Slits for Speedgrow™ Green Slabs

Good drainage slits in polythene wrap are vital since the excess water must be able to drain freely from the slab. Be sure to get this job done properly from the beginning!

  • Make sure you cut the slits in the slabs before planting!

  • The best position for these slits is between the plants and at the lowest point of the slab. Work vertically from the bottom up.

  • Vertical Drain Slits must be at least 1.2in Long

  • Horizontal Drain Slits (for roses) must be 4 – 6in Long and every 20 – 24in

  • Try to make the edges of the slits rough, this prevents them from re-sealing/clogging

Speedgrow Growing Tips - Drainage Slits Diagram

Speedgrow™ Green Plug Trays Techniques

Speedgrow™ Green Plug Trays are an excellent way to get your plants and crops started.

Soak the plugs long enough until they become fully saturated.

Insert 1-2 seeds or one cutting per plug. Thin seedlings down to one per plug after germination.

For optimal seedling growth, move plug tray to an area with medium light intensity and high humidity, such as under a clear dome with supplemental lighting.

Check regularly for any plugs that are beginning to dry and mist or irrigate lightly. Continue to monitor and irrigate as needed while plants grow. Avoid allowing plugs to remain soaking wet.

Fertilize with a low concentration of appropriate fertilizer based on the crop. A higher concentration can be used as the plant grows larger.

Once the plant is well grown and is fully rooted in the plug, it’s time to transplant! Insert the plug into a Speedgrow™ Green Cube or transplant in a larger pot or your garden.

Growing Techniques

Some tips and techniques to get you growing strong and healthy plants

As soon as the roots have penetrated well into the slab or big cube, the watering should be adjusted bearing in mind the following:

  • Check the quantity of drain on a regular basis (30-50% depending on the crop)

  • Start watering when transpiration has started

  • Stop watering at least 2 hours before sunset – On grey days (low light levels) even earlier.

  • The time to stop and amount of water is dependent on the weather, crop and irrigation strategy.

Check regularly for any cubes that are beginning to dry and need more water. Irrigation can be done by hand watering, emitters or flood irrigation. Continue to monitor and irrigate with appropriate nutrient solution as needed while plants grow.

Proper light levels are required for healthy and strong plants. Be sure to use the appropriate lighting system for the type of crop you are growing.

  • The Speedgrow™ Green 1.5in plugs are designed to transition smoothly into the Speedgrow™ Green Starter Cubes or Big Cubes and then into the Speedgrow™ Green Slab.

  • Insert the plug or cube into the hole on top of your Speedgrow™ Green cube or slab and tamp in lightly. Do not push the plug all the way into the edge, but leave about a 1/2 inch to stick out.

  • When placing Speedgrow™ Green cubes on big cubes or slabs they should be watered frequently to assure a good start to rooting. This allows for the roots to expand from the cube into the big cube or slab.

When the plant is fully established you are able to transplant simply by placing the Speedgrow™ Green cube or slab directly in a pot with additional growing media or in the garden as desired.

Watering Techniques

After a period of controlling the crop, it is important to keep enough strength for growth, both of the plant and its fruit and flowers. From this period, it is important to give enough water to achieve the desired drain. The total amount of drain (per day) must be between 30 and 50% (depending on the crop). To change the water content and EC level of the slab, the following water techniques can be used.

  • Watering with a higher frequency

  • Start watering earlier in the day

  • Stop watering later in the day

  • Night watering in shifts

  • Watering with a lower frequency and longer intervals

  • Start watering later in the day

  • Stop watering earlier in the day

  • No watering at night

  • Higher EC (fertilizer) input

  • Smaller shifts and intervals

  • Less drain

  • Lower EC (fertilizer) input

  • Larger shifts and intervals

  • More Drain