Madagascan Bat Guano

Description

High-phosphate Madagascan Bat guano is particularly important as it provides organic phosphate in both readily accessible and slower release forms at a level which is rare in truly organic fertilisers.

While nitrogen is important during the cannabis plant’s vegetative growth stage and it always likes good levels of potassium, our guano provides that abundance of organic phosphate which cannabis loves during and toward the end of its flowering period. Phosphate is also important for root development at the beginning of the plant’s life-cycle.

Critically important when growing organically with bat guano is that the phosphate is in a form very highly accessible to beneficial mycorrhizal fungi which should be utilised in symbiosis.

Use it as an amendment when first preparing your soil at the rate of 1 tablespoon (15 mls) per litre of soil. (Use more if you like, it won’t burn the plants like a chemical fertiliser. Some internet sources recommend double this amount.) Use a purchased “super-soil” or put together your own soil combination.

An excellent soil mix is 4 parts good quality potting soil to 1 part fresh vermi-compost (or substitute normal compost if you really can’t get vermi-compost), 1 part composted manure (chicken litter pellets are widely available but any well composted manure will do) 2 parts coco coir (well washed) and 1 part perlite or vermiculite.

Madagascan Bat Guano Grow Your Own Cannabis.

Add the guano, as recommended above, and crushed dolomitic lime at a rate of around 5 to 7.5 mls per litre of soil. Guano and some other organic fertilisers can be mildly acidic. Healthy soils regulate their PH naturally and cannabis likes acidity, but crushed dolomite helps buffer any excess and releases calcium and magnesium.

It is a basic agricultural item and every garden centre or nursery near you will stock it. This is particularly important if you are using fish emulsion as a supplementary feed as it can be very acidic. Volcanic rock dust and dried kelp meal are also beneficial but are not essential.

Inoculate with mycorrhizal fungus spores. This is highly recommended. A good way is to dust the root ball of your cutting or seedling with the spores as you plant them in the soil. If planting seed directly dig the spores in around the planting site before planting. (If using Trichoderma (harzianum or asperellum) don’t add them at this stage. Allow the mycorrhizae at least 2-3 weeks to colonise the plant’s root systems before introducing them.)

Your young cuttings or seedlings will thrive in this mix. The guano breaks down and the phosphate drives root growth. Supplementary feeding with aerated compost and manure teas, lucerne tea and kelp, fish emulsion/hydrolysate, seabird guanos, blackstrap molasses, concentrated molasses sollubles (cms) etc will boost N and K and ensure explosive all-round growth.

Worm tea and other microbial additions are very beneficial. You can be as elaborate or as simple as you want. (You can make fish emulsion and molasses or cms your easy, go-to, supplementary feed and get more creative as and when you have the inclination and time.)

For grows with a relatively long vegetative growth period (more than 4-5 weeks) you may want to give the Madagascan Bat guano a boost with top-dressings during the vegetative stage. (See the top-dressing instructions under flowering.) For long outdoor grows which may veg for several months, use your discretion.

If you are growing indoor cannabis the plants will start to flower when you switch your lights to 12hrs light/dark. Outdoor plants will start to flower as the days begin to shorten in late summer. Auto-flowering depends on the strain but they will usually start flowering when they are around 4-5 weeks old.

By now, unless you have a very short vegetative growth period, much of the initial guano will have broken down and a top-dressing is needed. The amount depends on the size of the plant and its root spread. Where plants are restricted to pots, cover the surface of the soil in the pot to a depth of around 4 millimeters and dig lightly into the surface of the soil.

This is a general rule and it is difficult to give exact amounts. Bigger plants in small pots may need more and small plants in big pots less. The healthier and more vigorous your plants are, the more nutrient they will use and the more heavily you should feed.

The roots of plants grown directly in the ground are less restricted and will usually coincide more or less with the extremities of the plant canopy. Digging in from the plant stem to about 80% of the distance to the outer leaves is sufficient.

As you water and feed, the guano will break down and release its goodness. Maintain supplementary feeding as before for around two weeks after the start of flower as the plants stretch to their final height, but then cut the nitrogen-heavy feeds such as fish emulsion, seabird guanos and nitrogen-rich manures to around one third of your feeding or the plants will put too much energy into leaf production.

Legal Cannabis:

3-4 weeks before your anticipated harvest date stop any supplementary nitrogen feeding completely. Top dress again with bat guano (it has enough N to carry the plants through to the end) and supplementary feed only with low N, high K feeds such as molasses, kelp and cms (and other fast-release organic high P or K feeds, if you are sure they are organic). Stop all supplementary feeding a week before harvest and water only. If you have your timing right, the plants are shutting down and you are just wasting nutrients.

Throughout this process you can supplement your teas or nutrient solutions with guano at around 1 tablespoon per litre, or more. Allow it to steep in water or a compost or other tea for 24 hours with good aeration then add whatever else you are using and feed. With strains which take longer than 8 weeks to flower you should incorporate an extra top-dressing before the end of the flowering period. (So, for a 9-week flowering strain: once a week zero, once a week 3 and again at week 6.)