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matt_barnett67

Good "compromise soil" mix?

Matt Barnett
5 years ago

After reading the wealth of information on Al's soils post, I am ready to step out of the store-bought soils and get into something that will be better long-term for my plants. Based on what I have been reading, there is a difference between what is best for the plant and convenient for the grower. The plant wants something that drains instantly and needs to be watered daily. Growers want to water as infrequently as possible, which means the soil should capture and retain water, which is not very good for roots.


I want to mix a soil that will allow me to (with a little preparation) take a week vacation and not come back to dead plants. I have used Spanish moss as surface cover on plants that are particularly thirsty to add a little time between waterings, and I suppose that would be an acceptable compromise if I had to be out of town for a week. As I live in Florida, Spanish moss is fairly dripping from trees and could be collected by the bushel in a couple minutes.


I know each plant has it's own preferences, so excluding the succulents on one side of the spectrum and plants that want their feet continuously wet on the other, what would be the components and proportions of a quality soil mix for the majority of houseplants?

Comments (11)

  • gardengal48 (PNW Z8/9)
    5 years ago

    I use the 5-1-1 mix. It certainly does not require me to water houseplants on a daily basis......in some cases it is a week or more between waterings, longer in winter.

  • jane__ny
    5 years ago

    It would help if you tell us what you are growing.

    I live in Florida, Sarasota. I have a few hundred orchids and a bunch of 'dirt' plants.

    On the dirt plants, I pot in a mix of potting mix, wood chips, perlite. You can use sphagnum moss as a top dressing if you worry about the surface drying out too much. I do that on a lot of my orchids.

    This time of year in Florida is rainy. I would not top dress with sphag unless your pots drain quickly. I would never recommend Spanish Moss. Sphagnum moss is much better.

    We leave for two weeks every few months. I've never lost a plant. I water well before I leave. Pull some into shady spots and hope for the best. So far, so good!

    Jane

  • Sage TX 9a
    5 years ago

    Indoor temp is another major factor. Between May and September, I'm lucky if the house cools down to 77 at night and doesn't heat up above 83 on days when it's 102 outside. But I've got wood and brick siding on an old house, not hardiplank and quarried stone, which do a lot better against the south Texas heat. Given the givens, 5-1-1 dries out too fast for my needs.

    That said, if all you need is a vacation watering strategy, use wicks. Cut a length of nylon (not cotton -- it must be synthetic) clothesline. Bury one end in the top of a potted plant, so a few inches lay flat under the surface. Put the other end in a big bowl of water. Repeat. Maybe cover the bowl with a loose fitting lid to reduce evaporation. Obviously you wouldn't want to leave them like this permanently, but it will keep them alive for a week easily.

  • toxcrusadr
    5 years ago

    Does it matter if the bowl is on the ground next to the pot, or does it have to be level with it, or above it?

  • Sage TX 9a
    5 years ago

    It's less a matter of the level than the length of the wick. I *think* I read that the wick needs to be no longer than 11 inches from surface of the water to the surface of the target soil, as there's a limit to how far clothesline will actually wick a fluid. I've never seen a comparison of reservoir elevations, but maybe there's one out there?

  • toxcrusadr
    5 years ago

    I would think it would have a drastic effect on the rate.

  • Sage TX 9a
    5 years ago

    Maybe? I don't know much about fluid dynamics. Feel free to do an experiment and let us know the results!

  • petrushka (7b)
    5 years ago
    last modified: 5 years ago

    i use 3/8" nylon braided rope with acrylic core as a top wick for my plants in large pots when i go away. it's a good idea to have reservoir next to plant pot as close as you can make it on the same level. so as to reduce the air-exposed portion of the wick . for small 5-7" pots you can use detergent jars (1.5 qt), they are sturdy and high enough and opening is narrow, so when the water levels drop the wick will still be inside and wicking.

    open water reservoirs are not so good - too much water evaporation.

    water or vinegar 1 gal jars are very good too for med sized pots.

    for very large and thirsty plants i use 20qt water-jugs - they can be refilled from top, if you cut a 1" hole on top (you drop sev wicks inside).

    when the plants are thirsty i dig in the wick all the way around the perimeter of the potabout 1-1.5" below the surface for good contact with soil.

    you can use this type of wicks on succulents too -i have many in clay pots - i just dig in half of the perimeter then. i find that pushing them around the perimeter gives roots better access to water then just pushing the wick in one spot but deeper.

    also it's best if water-jar is not translucent as sunlight will bring algae. it helps to control that by adding 3% peroxide to water, about 1tb per gallon.

  • petrushka (7b)
    5 years ago
    last modified: 5 years ago

    as far as soil mix for wicking - for the best results with wicks soil mix needs to be at least 40% peat or coir-dust (coir peat) and 40% perlite to alow sufficient aeration of roots when medium is constantly moist (although it will get drier in top 1/3 of the pot, the bottom will still have moisture). the rest can be bark or coco-chips. for very thirsty plants peat/coir can be increased to may be 60% of the mix.

    standard houseplant mix (peat based) mixed with perlite 1:1 is sufficient for small plants in 6" pots.

  • Matt Barnett
    Original Author
    5 years ago
    last modified: 5 years ago

    When I am trying to source pine bark, being in Florida, I can find a lot of this bark

    From these longleaf pines

    It is very flaky, and peels apart like onion layers or pastry. Will this bark work or do I need the northern shortleaf pines that have nugget bark?

  • Sage TX 9a
    5 years ago

    No, you're looking for Fir Bark Fines, which are evidently easy to get if you live up north. I'm in San Antonio, and I don't trust the big box store's alleged "decomposed pine mulch" to be either pine or decomposed. I'm also not strong enough to heft a giant bag of it and then sift it into a wheelbarrow, so I just get Reptibark instead (compare Amazon and local pet stores for the best prices).