What type fertilizer do peace lilies like?

(Linny) Salem, SC(Zone 7b)

My florist quality peace lily has not blooomed a bit since I divided it into two plants. What can I fertilize them with to get them to bloom again?

Thanks, Linny

(Zone 1)

Try a fertilizer with a high middle number. I use orchid fertilizer 11-35-15 on my Peace Lily.

Dublin, CA(Zone 9a)

How long ago did you divide and repot? When you do that it'll often take a while before it'll bloom again--needs time to develop roots, etc first

Bay City, MI(Zone 6a)

Oh boy! I think so highly of Lin, that I hate to disagree with her about the high-P (middle number) fertilizer. Will you forgive me, Lin?

Here's the deal: It may surprise you to learn that almost all plants use nutrients in roughly the same ratio, that being about 10:1.5:7 NPK. So for every 10 parts of nitrogen (N) they use, they only use 1.5 parts of phosphorous (P). When you analyze the tissue of plants, you'll also find roughly these ratios in all plant parts - including leaves/blooms/fruit .....

Another surprise is that Lin's 11-35-15 fertilizer doesn't really contain as much P as you think, but it still contains MUCH more P than the plant could ever hope to use in relation to both N and K (potassium). The P in fertilizers is reported as P2O5 (phosphorous pentoxide), but P205 is only 43% P. We know that plants use 6X more N than P, and when we do a quick calculation, we can see that 11-35-15 is ACTUALLY about 15% P. I hope you're still with me.

If plants use 1/6 as much P as N, and we want to supply as much P as plants actually use, we would divide 11 by 6 to see that ideally, fertilizers with 11% N would only have about 1.8% P. Since Lin's fertilizer supplies 15% P, it is supplying more than 8X more actual P than her plants can use.

So what's the disadvantage? Let me start by saying you can't force a plant to take up more P than it needs by virtue of the fact you supply extra. It will still take what it needs and leave the rest. The 'extra' isn't just 'wasted'; its disadvantage comes in the form of the influence the excess has on the chemistry of the soil solution. Excess P in soils limits the plants ability to take up several other elements ( causes antagonistic deficiencies), particularly Fe (iron) and Mn (manganese). It contributes unnecessarily to the EC/TDS (roughly the salt levels of the soil) which makes it more difficult for the plant to take up water and all other nutrients that must be dissolved in that water. Liebig's Law of the Minimum addresses the issue of excess nutrients in the soil and states that excesses (toxicities) are as limiting (to growth and vitality) as deficiencies.

From this, we can draw the conclusion that for best growth and vitality, it is to our benefit to supply nutrients in as close to the same RATIO that plants actually use them in. When the factoring is all done, the closest ratio commonly available, and the one that allows us to keep the o/a nutrient level at its lowest w/o nutritional deficiencies is a 3:1:2 ratio. I capitalized 'ratio' earlier because a ratio is different from the fertilizers NPK %s. Examples of fertilizers that supply NPK in 3:1:2 ratios are, Miracle-Gro/Peters/others in NPK %s of 24-8-16 (soluble granular), Miracle-Gro 12-4-8 liquid, and my favorite - Foliage-Pro 9-3-6 liquid.

As far as manipulating your plant's nutrition to help promote blooming, for more prolific flowering, a reduced N supply will have more and better effect than the high P bloom formulas. When N is reduced, it slows vegetative growth without reducing photosynthesis. Since vegetative growth is limited by a lack of N, and the photosynthetic machinery continues to turn out food, it leaves an expendable surplus for the plant to spend on flowers and fruit.

I also agree with Ecrane, in that recently transplanted PLs will often sulk for a while until they get their feet under them (reestablish their root mass) ..... plus the fact that most but not all PLs tend to be more prolific bloomers in the summer.

I hope that made sense. If you're interested enough that it left you with questions, please ask. A good soil is also a very important consideration for PLs. The roots are the heart of the plant, and if the roots ain't happy - ain't no part of the plant happy! ;o) Enough light is also an important factor in determining how prolifically they bloom.


Thumbnail by tapla
(Linny) Salem, SC(Zone 7b)

Sorry it has taken me so long to get back... please don't think I don't appreciate all your advice.. just have a full plate right now.

The peace lilies seem to be okay. Putting out lots of new leaves. Guess they will bloom when they get ready.

Peace - Linny

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