How To Make The Best Fertilizer For Cactus

You may not be as familiar with manure tea as you are with compost tea, but if you want your cactus plants (Cactaceae) to thrive, you should remedy that. Cactus plants need very little fertilizer, and if you use the right manure, manure tea provides one of the best fertilizers for cactus, with a balanced blend of nutrients that won't overwhelm your succulents and make them grow out of their pots. If you have access to cow, horse or sheep manure, you can make fresh manure tea in a bucket. If you're a city slicker, don't worry ... you can make your manure tea with commercial tea bags just as you do your morning cuppa.

The three components of commercial fertilizers are nitrogen (N), phosphorous (P) and potassium (K), and their ratio, known as the NPK ratio, is listed on the container. Plants use nitrogen to grow lush greenery for photosynthesis, phosphorous to grow strong roots and potassium for overall health. A cactus doesn't have leaves and performs photosynthesis through its stalk, spines or branches, so if it takes in too much nitrogen, it grows more quickly and may soon outgrow its container.

When fertilizing cactus with a commercial fertilizer, the usual protocol is to dilute the fertilizer to half or quarter strength to avoid overdoing the nitrogen. As an alternative, you can use a fertilizer made for cacti, which often has a lower nitrogen percentage than phosphorous because cacti need phosphorous for root growth. Schultz Cactus Plus, for example, is a 2-7-7 blend that provides nourishment for roots and disease resistance while keeping the nitrogen to a minimum.

Manure tea is high in nutrients without containing excessive amounts of nitrogen depending on the type of manure you use. Cow and horse manure are best for cacti and succulents followed by sheep and goat manure, while chicken and pig manure are less ideal because of their high nitrogen concentration. Manure tea is completely organic, and it drains quickly through the soil rather than soaking in as a granular fertilizer would, so there is less danger of overloading the cacti with nitrogen. Whether you use fresh-cured manure or purchase manure tea bags, it's inexpensive and easy to make yourself.

If you're using commercial manure tea bags, simply follow the directions on the container. They will specify the amount of water to use and how long to let each bag steep in the water, which is typically two to three days. Once the tea is ready, you use it to water the cactus.

If you're making manure tea using fresh manure, you need to cure the manure by piling it in the yard and periodically mixing it with water and organic matter until it turns crumbly and soillike. You don't need much manure to feed cacti, and manure tea keeps only for a week or so, so you can probably make enough for your cactus garden in a 1-gallon paint bucket. You'll also need a filter bag; an unused 1-gallon paint strainer should work well.

Put the strainer in the bucket and shovel in some manure. Add water at a ratio of 2 parts water to 1 part manure. When the bucket is full, cover it and let the mixture steep for about a week. At the end of the week — and this is the messy part — you have to remove the strainer and squeeze the contents into the bucket, so be sure to wear rubber gloves. The tea will be dark brown, and you'll want to dilute it to the color of weak English breakfast tea before you use it.