The Expert Way to Hydrate Coco Peat

Coco peat, the gardeners most efficient grow medium, is generally shipped in a compressed block or disc. Just add water and plant, right? While that’s the basic process, a “slow and steady wins the race” approach produces the best results. Here are some of HortGrow’s “Best Practices” for gardening success.

Hydrating Coco Blocks

HortGrow coco peat grow mixes are 5 kilo blocks, shipped in a sturdy tote for ease of handling in your planting area or patio. Snip the ends of the string closure and pull – – – when you pick the right end, the chain stitches will zip right out, exposing the block.

When hydrated, a single block will fill an entire wheelbarrow with fluffy planting mix, but the blocks may also be placed in a large container or on the ground before adding water.

It takes between 4-5 gallons of water to hydrate a 5 kilo block of coco coir. Because the texture of the blocks is very firm, you will need to be prepared initially for the water to run across the surface and down the sides of the block. In other words, you’ll need to hydrate in a container or on the ground where the water can collect around the block. If you do not have a wheelbarrow or garden cart, or are gardening in a small patio or balcony, a standard 16-20 gallon storage tub will work fine, and will also store any excess planting mix you don’t use. Coco Peat is virtually odor-free, so indoor storage is not a problem.

Start by adding the water, about a gallon at a time, pausing for a few minutes between applications. The coir fluffs up and becomes pliable as it absorbs the water. (If there are youngsters around, this initial step is fun for them to watch, as the block will actually “bloom” in slow motion right before their eyes!).

As each few inches of the block hydrates, you can speed up the process by brushing the top layer aside before applying another gallon of water. It takes about 15-20 minutes of watering and pausing to prepare about 2.5 cu. ft. of ready-to-plant coco potting mix.

What happens if you add too much water?

One of the attributes that makes Coco Peat such an amazing growing media is its outstanding water-retention ability—10 times its weight on average. However, even coco has its limits, and if you are using a constantly flowing hose for the hydrating process, it is easy to over-saturate the block.

When this happens, the excess water will pool and not be absorbed. Unlike peat moss or other soil mixes, where you would just have to wait till the water evaporated, this problem is easily remedied by shoveling the wet coco mix into any container with drain holes in the bottom. It’s basically the same technique as using a colander to drain pasta in the kitchen…excess water goes out, leaving the perfect ingredient behind.

The excess water instantly drains out of the bottom of the container and in about 5 minutes your mix will be fluffy and ready to plant.

This process also demonstrates one of the most incredible qualities of coco coir potting mixes: if your container or patio pot has drainage, it is virtually impossible to over-water your plants. As oxygenating roots is as important to plant health as feeding and watering them, coco peat’s natural qualities automatically balances the aeration/hydration in the container every time you add liquid.

What if I do not need the whole block?

Suppose you are going to start a small group of succulents from cuttings, and only need a small portion of GrowSure, the fine coco pith potting mix recommended for propagation. There are two ways you can use a partial block.

Method 1: Cut or break off a portion of the dry block.

Coco blocks can be cut with a hand or electric saw, in the same way you would cut a log or a piece of wood. Once a section is cut off, other small pieces are relatively easy to break off, and you can hydrate the small pieces and save the rest in the cloth tote the block was shipped in. Because of the air spaces created within the chunky mixes like GrowUltra and GrowExcel, it is relatively easy to insert a trowel or spade into the sides of the block and break off pieces until you obtain the desired volume.

Method 2: Water a small corner area of the block

If using a saw or blade is not your skill set, you can water one corner of the block and crumble off the desired amount of Coco Fiber for your needs. This is best accomplished with a gallon jug or watering can so you have more control of the wet and dry portions. Once you have collected the desired amount of coco mix, return the block to its tote and store for later use.

As HortGrow’s coco coir mixes are formulated for specific types of plants, each type will hydrate a bit differently. GrowMax and GrowUltra for example, are different combinations of fine textured coco pith, ground coco fiber, as well as some chunky coco chips and shards. This kind of combination provides maximum aeration over a long period of time, making it the choice for long duration plants like perennials—dwarf citrus, hibiscus, potted palms, roses and berries. Because the fibers and chunks are more dense, you will have best success hydrating these mixes a bit in advance of use and fluff them with a trowel or garden fork. Depending on the season and your climate, you might need to add a bit more water after an hour or so as the larger coco portions will re-hydrate more slowly.

In fine textured mixes, like GrowSure and GrowPlus, the water distributes quickly and the potting medium is fluffy and ready for seedlings, cuttings, or as top dressing in less than 30 minutes.

Hydrating Coco Discs in Grow Pots

HortGrow’s GreenEra Grow bags are the quick and very tidy way to garden inside or out. The sturdy felt pots are shipped with large gradient discs that expand to fill the pots to capacity.

The bottom disc, comprised primarily of coco chips and coco fibers is designed for maximum aeration and is placed rough side down in the bottom of the bag. You will gradually add water, wait about 5 minutes and the disc will slowly expand to fill the bottom ½ of the pot. The second disc, also a gradient of coarser to finer media is then placed on top of the hydrated coco peat and gently watered.

Once the second disc expands to fill the entire pot – less than 5 minutes-it is ready for planting. The total time from opening the GreenEra pot package to your finished patio “Salsa Garden” for example, (Tomato, jalapeno, cilantro, garlic and mint pictured below) is less than 30 minutes, and absolutely no clean-up required.



Because HortGrow felt grow pots and grow bags are breathable, the Coco Peat potting mix cannot be overwatered, as the excess will drain away immediately. However, if you are filling pots on a terrace or balcony, its best to place a large saucer under the aeration grate underneath the pot to avoid dripping on the neighbors downstairs!

Unlike the complicated formulas circulated for preparing ordinary container gardens, you do not have to do additional preparation before planting seeds or plants. No rocks in the bottom, no sand, wood chips, compost, and no purchase of soil or peat moss. You just add water, fluff the top layer, and plant. GreenEra Grow Bags can be used as stand-alone gardens, or placed inside decorative patio pots for a more stylish appearance.

All HortGrow compressed blocks and discs are OMRI listed, sustainably sourced and eco-friendly. This fluffy medium is easy to work with, does not stain hands or nails, and will last for 5 years or more. All mixes and GreenEra grow pots are available at HortGrow Amazon.

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