Bottom Watering and Fertilizing

[parke.hk]

For bottom watering how often and how much should I be watering? I have been trying to keep about a quarter inch of water in the bottom of my flat at all times. Will this cause overwatering? Should I let it dry out? Is the amount of water needed based on the size/development of the seedlings? Would they need less water once they have true leaves?

I plan to use a seaweed fertilizer on my seedlings once they have true leaves. Should this be sprayed on or added via bottom watering?

[applestar]

You should not have any water sitting in the drip tray. When bottom watering, add water and let the soil soak up the water, then add some more if needed, but if there are any water left after 30 minutes, the extra water needs to be eliminated. This can be done by lifting the container with plants and pouring the water out of the bottom tray, or using something like an eye dropper -- turkey baster works well for large trays.

You'll learn how much they take up as you go and can provide just enough so you don't have the excess water to deal with any more.

[rainbowgardener]

I'm a little less hard core about it than applestar. I don't suck the water back. But I do NOT keep water in it at all times. I put just enough water in that it touches the soil to be wicked up, that 1/4 " or so, in the AM. If it hasn't all disappeared by evening, I don't give it more the next AM. I agree that you don't want them sitting in water all the time.

I don't mist seedlings, with anything. The point of the water restriction is that seedlings are very vulnerable to fungal diseases like damping off. I think misting makes that more so. If you want to feed them (if your potting soil has nutrients in it, you don't need to), put it in the water for bottom watering.

[lily51]

One thing to watch with bottom watering is that as the water moves up to surface it brings with it salts , etc in the soil and fertilizer. If these get concentrated in the roots plants can be damaged. Watch for accumulation on surface.

[DoubleDogFarm]

One thing to watch with bottom watering is that as the water moves up to surface it brings with it salts , etc in the soil and fertilizer. If these get concentrated in the roots plants can be damaged. Watch for accumulation on surface.

Never had a salt build up problem. I don't use synthetic fertilizers.

Eric

[parke.hk]

Good to know that I was only overwatering my onions. Once I start my peppers, tomatoes, broccoli I will water them correctly.
I do have seed starting soil, so it seems as though I probably don't need fertilizer until their in the garden.

[lily51]

That's good doubledog. With soiless mix for seed starting you'll have
Less chance,too, for soluble compounds to accumulate.
What fertilizer do u use?
All my plants do well, except each year there's the Mg deficiency problem with the geraniums I start due to our well water composition.
One dip in weak solution of magnesium sulfate has worked and now I have fertilizer with Mg compound in it, so we'll see what that does.
Am always looking for new ideas.

[rainbowgardener]

"I do have seed starting soil, so it seems as though I probably don't need fertilizer until they're in the garden."

Depends on what you mean by that. If by "seed starting soil" you mean potting soil with Miracle-Gro (or some other brand), that is true. If by "seed starting soil" you mean an actual seed starting mix (sold as such), those are usually sterile, without nutrients and you will need to fertilize or move them in to M-G potting soil.

[DoubleDogFarm]

That's good DoubleDog. With soiless mix for seed starting you'll have
Less chance,too, for soluble compounds to accumulate.
What fertilizer do u use?
All my plants do well, except each year there's the Mg deficiency problem with the geraniums I start due to our well water composition.
One dip in weak solution of magnesium sulfate has worked and now I have fertilizer with Mg compound in it, so we'll see what that does.
Am always looking for new ideas.

This years mix is 2-Coir, 2-Perlite, 1-Sand, 1-Fine compost. I sift the sand and compost with 1/8" hardware cloth.

I use pond water, hydrolyze fish and manure tea. There is potential for some salt build up, but over the years no major problem.

Every gardener has to make choices. For me, no Scott's Company products will ever inter my property unless I'm duped.

Eric

[rainbowgardener]

Thanks for posting the mix... I will get there. I swore I wouldn't use the M-G potting soil this year, but then I didn't get it together to find coir and perlite in time for seed starting. During this season I will figure it all out and be sure to have home made soil sitting ready next time!

One of the things about gardening in the inner city is that there are no garden stores closer than a half hr drive to me. All those places are out in suburbia where people have an acre of lawn. I have to either mail order stuff like that or drive an hour round trip to get it. But I will get it together!

[lily51]

Thanks for the mix ratios. Would tis mix be good for succulents or would more sand be needed?

[DoubleDogFarm]

Sorry, I can't answer the succulent question. I could look it up. Maybe Kisal or someone familiar with this type of plant will come along.

Eric

[DoubleDogFarm]

Soil: Cactus and succulent potting mixes are sometimes available commercially, but many people like to create their own special mix for their plants. There are some basic characteristics that a potting mix for cacti and succulents should possess. Perhaps the most important characteristic is that the soil should drain very well. The best way to achieve this is by adding horticultural-grade sand and grit to the compost component of the soil. Many believe that a good starting ratio for the mix's components are one-third compost, one-third horticultural-grade sand, and one-third grit.

For the compost component, a growing number of hobbyists believe that a peat-based compost should not be used, as it seems to contribute to pest problems like 'root mealy bug' and 'fungus gnat', and doesn't contribute much in the way of nutrients to the plant. Many people start with a good grade commercial potting mix for the compost component, and some sift it through a screen to remove such "undesirables" as the small pieces of wood and twigs that can sometimes be found in such mixes.

All sand is not created equal. The sand component should be horticultural grade, relatively coarse, and sharp. Never use non-horticultural grade sand, such as fill sand, as this is usually not washed, and can contain, among other things, salt.

For the grit component, most people agree that horticultural pumice is the best. It is also not widely available, and can be expensive if you can find it. Some other materials that can be used include pearlite, porous gravel, and lava fines. People often have good luck using fired clay products for the grit component. These products include certain cat litters and products that are used to absorb oil spills. If using one of the clay products, you must ensure that it is a fired clay that does not break down and turn to mush when it gets wet. Check the labeling, and to be sure, test it out by putting some in a jar of water for some time to see if it breaks down. Mush in your potting mix will do your plants no good.

Like everything else discussed so far, there are no hard and fast rules for potting mixes, so you'll need to experiment with ratios. The above ratio of components represents a good starting point.

https://www.csssj.org/welcome_visitors/basic_culture.html

Eric

[lily51]

Thanks!