Of all the aquarium plants out there, Amazon Sword Plants are some of the most instantly recognizable!
Showy, vibrant in color, and with broad, beautiful leaves, they are fairly easy to care for and make for a great focal point in most aquascapes.
There are a few details to be aware of but if you want to try a large, impressive live plant for your first planted aquascape, Amazon Swords are some of the best species to start with!
Getting to Know Amazon Sword
As the name suggests, the Echinodorus family is heavily concentrated in the Amazon River basin, giving you an idea of the conditions they prefer.
However, the entire family is actually scattered all over both North and South America.
Many do well even in temperate conditions like those found in most of North America.
Amazon Swords get their name from their broad sword-shaped leaves, which is also classic to the family.
These are medium to large plants, for the most part, many reaching up to 2 feet in height. While they are very easy to care for, Amazon Sword Plants are very hungry for light and nutrients. At a minimum, you’ll want to provide them with ample lighting and either proper aquarium aqua soil or regular fertilization.
- Scientific Names: Echinodorus sp. (ex: bleheri, tenellus, ozelot, etc)
- Origin: North & South America
- Size: variable: anywhere from 2 to 24+ inches
- Ease of Care: Easy
- Growth Rate: Moderate
- Light Requirements: Moderate to High
- Fertilization Needs: High
- Carbon Dioxide Needs: Preferred but not Required
Types of Amazon Sword Plants
The name “Amazon Sword Plant” is actually used interchangeably to describe the entire group of plants in this group as well as a smaller group of similarly sized members.
There are around a dozen species that can be found in the hobby commonly, with new varieties of each of these plants popping up every year!
But these are the four you will most likely run into at your local fish store!
Amazon Sword Plant
This plant often goes by Echinodorus amazonicus, Echinodorus grisebachii, and Echinodorus bleheri. The jury is still out whether these are separate species or synonyms for a single plant. Botanists have a hard time classifying plans because species boundaries aren’t as clear cut as they are with animals.
Still, the “classic” Amazon Sword Plant is the most popular of the group and the one I will be discussing most often in this care guide!
Dwarf Chain Sword Plant
The Dwarf Chain Sword Plant goes by the name Echinodorus/Helanthium tenellum and is found throughout North America as far north as Michigan and Massachusetts all the way down to Argentina in South America. It is a hardy carpeting sword plant that only grows a few inches tall.
Dwarf Chain Swords are aggressive spreaders when the conditions are right. They need strong lighting since they grow near the bottom. But when given enough light and a rich substrate they will send runners out in all directions, cloning themselves to colonize as much of the bottom as possible! They are not nearly as difficult to care for as other carpeting plants and are a great choice for beginners!
Melon Sword Plant
Melon Sword Plants are popular due to their distinctly rounded leaves, which are radically different from the sword-shaped leaves that are common to the family. They are also as showy as classic sword plants, growing up to 20 inches tall. Melon Sword Plants make great showpiece specimens for larger aquariums that have room for them to grow tall. Many have both green and red leaves but the red usually fades as teh leaves grow larger. When kept in high light conditions and enriched with CO2 the leaves may remain red even into maturity!
Micro Sword Plant
Brazilian Micro Sword Plants (Lilaeopsis brasiliensis) are very easy to find in most aquarium specialty stores. Unfortunately, they are one of the more difficult plants to grow and the vast majority die if not well cared for.
They are actually not related to true sword plants at all, they simply look superficially the same. Brazilian micro Swords need at least moderate lighting but really thrive under high light conditions. A rich, fine grained substrate and carbon dioxide also encourages them to spread. Despite how cheap and easy to find they are Brazilian Micro Swords are better for intermediate to expert level aquatic plant keepers.
Lighting for Amazon Sword Plants
Amazon Sword Plants are medium to high light plants. If you prefer a more compact growth form then keeping them in high light conditions will help encourage them to grow laterally somewhat. But as a general rule sword plants are fairly tall plants and will likely take up a lot of vertical real estate.
What’s most important is ensuring your light is of the right spectrum. You need photosynthetically active radiation (PAR) when keeping Amazon Sword Plants – or indeed, most aquarium plants. PAR is what helps plants crack apart carbon dioxide and water to create oxygen and simple sugars.
Even if you have multiple incandescent fixtures, which are often found in older aquarium hoods, the light is of the wrong spectrum and mostly useless for your plants.
Full-spectrum fluorescent, LED, and power compact bulbs are the most efficient. LEDs used to be too expensive for any but advanced aquarists but have now become extremely affordable. LEDs are not only energy-efficient but also much cooler running than incandescent or fluorescent lighting.
As far as hours per day, anywhere from 8 to 12 hours is best for these light-hungry plants. You might decide to lower the amount of light if you have algae issues but generally speaking, more light is better, helping them to spread and put out additional growth.
It is best to stick to a lighting regimen once you’ve decided on one. Continually changing how many hours of light per day Amazon Sword Plants receive can cause many problems in your tank.
For one, plants are used to the slow changes of seasons and adapt their metabolisms in response to light. They have trouble performing basic regulatory functions when light levels are continually shifting.
Shifting light and plant functions also mean that your aquatic plants won’t be able to process excess nutrients and carbon dioxide as efficiently. This leads to algae issues coming up. Unfortunately, most aquarists reach right for a bottle of algaecide when simply waiting for your plants to rebalance is a better solution.
Substrates for Amazon Sword Plants
Amazon Sword Plants are a prime example of root-feeding plants. While they do uptake nutrients through their leaves like most aquatic plants, they preferentially uptake them through their roots. So water-borne fertilizers aren’t quite as effective as substrate-based ones.
You can use plant root tablets placed near the base of a large sword plant or scattered around the tank so all of your plants can uptake the nutrients over time.
If you prefer water-based fertilizer dosing, using a substrate that has a high cation exchange capacity is recommended.
Substrates with a high CEC include baked clay and aqua soil. They have the ability to bind nutrients to themselves, holding onto them until plant roots uptake them. Inert substrates like gravel don’t bind nutrients. But a gravel grain on the right side will allow water to flow in between the grains, helping liquid fertilizers find their way down.
Amazon Sword Plant Fertilization Needs
What is most important is ensuring your aquarium plants are getting their macronutrients; the ones they need large quantities of to survive. These are the NPK trio: nitrogen, phosphorus, and potassium.
Nitrogen can come from several sources, with the most common being ammonia, nitrite, and nitrate. Amazon Sword Plants prefer ammonia but it is also the most toxic form of nitrogenous waste to fish. So most aquarium fertilizers use nitrate, which is well tolerated by fish.
A lack of nitrogen can be identified by new growth remaining as small, pale leaves rather than expanding and darkening over time.
Phosphorus is another essential nutrient that most aquarium fertilizers provide in the right amounts. If your phosphorus levels get too low the older leaves of your Amazon Sword Plant will start to yellow. Dead patches may form and other leaves may simply fall off, far too quickly to be normal shedding of old leaves.
If potassium levels are becoming too low you will start seeing tiny pin holes forming right in the middle of the leaves with yellow edges to them. Over time the holes will expand if no potassium is added to the system.
Iron deficiencies are also common in Amazon Sword Plants, identified by yellowing of the entire plant. So make sure that you test your macros + iron regularly in order to catch issues before they arise!
Do Amazon Sword Plants Need CO2?
Amazon Sword Plants don’t need carbon dioxide but they certainly love it. Carbon dioxide is often the limiting factor for most planted aquariums and enriching your water with CO2 can increase plant growth by as much as 5-10x, depending on the species!
Carbon is the foundational building block for plants, forming the very structure of their cell walls, leaves, and stems. And CO2 is their primary source of carbon. As anyone who knows middle school biology remembers, plants intake carbon dioxide exhaled from animals, releasing oxygen, which animals then inhale. So fish are a source of CO2 for aquarium plants. But not as much as you might think. And not nearly as much as can be provided by CO2 enrichment.
Liquid CO2 boosters like Seachem Excel actually work well with Amazon Sword Plants.
Some plants, like mosses and Cryptocoryne are stressed by the active ingredient but sword plants will show a nice boost in growth without needing to fuss with pricier CO2 injection systems.
Adding carbon dioxide also helps plants outcompete algae since their growth is no longer limited by available carbon. Algae needs much less CO2 than multicellular plants and will take up extra nutrients from fertilizer and available light if plants can’t grow fast enough to lock it away.
The topic of carbon dioxide also touches on growing Amazon Sword Plants out of the water. Believe it or not, many aquarium plants actually grow just fine exposed to air. Or to be fair, when kept wet and in high humidity conditions. Amazon Sword Plants tend to grow alongside river banks and in the splash zone, so they transition continually between the emersed and submerged states.
The benefit to growing Amazon Sword Plants out of the water is that the air we breathe has far more CO2 than water does.
It’s the foundation of the Dry Start Method, which relies on the unlimited CO2 of the atmosphere to help aquarium plants get established faster.
Once your sword plants and other aquarium plants that grow emersed get established, you can then flood the tank, starting out with a lush aquascape much faster than if you’d tried establishing the tank in the usual way!
Propagating Amazon Sword Plants
As beautiful as they are, an entire aquarium full of Amazon Sword Plants is the dream of many an eager aquarist.
Fortunately, they are also one of the easiest plants to propagate, requiring very minimal effort beyond providing them with ideal conditions.
Occasionally, your Amazon Sword Plant may flower if it is near the surface.
They are pollinated by bees in the wild. Since there probably aren’t many bees in your house you’ll need to pollinate them by hand if you’re interested in seeing how this developmental process unfolds.
Most aquarists rely on the second way that these plants reproduce. When happy with their conditions Amazon Sword Plants send runners out in all directions. These thread-like growths look like especially long roots with a little bud on the end. Sword plant runners may be above the substrate or below. And as they extend you’ll see baby sword plants growing along the “line.”
These are clones of the original and help it to colonize fresh living space as quickly as possible. These young sword plants can be left attached to the runner for as long as you wish; they will draw nutrients from their parents before eventually growing large enough to fend for themselves.
Once the plant is a couple inches tall and has at least 4 leaves you can clip free the baby sword plant using sharp planting scissors and replant it elsewhere or give it to friends.
Never use paper shears or other tools not meant for aquarium plant use; they are usually dull and wil crush plant tissue.
Crushed tissue doesn’t always recover properly and often becomes infected by bacteria, which can kill your plant.
Amazon Sword Plant FAQ
“Classic” Amazon Sword Plants are very tall specimens, reaching anywhere from 16 to 24 inches in height. Many of their relatives, including the Melon Sword, also grow quite tall, while others, such as the Pygmy Chain Sword, stay closer to the substrate.
Amazon Sword Plants are not floating plants. They are also predominantly root feeders and would eventually die if left floating for an extended period.
Yes they can! They grow alongside rivers in the wild and can grow both submerged and emersed! Amazon Sword Plants are ideal for terrariums for this reason, giving frogs, salamanders, and other semi-aquatic animals dry perches to live on!
Amazon Sword Plants need at least medium light levels to thrive. They may not die if the low light is of the right spectrum but they won’t do much growing in these conditions.