Liquid fertilisers are a great way to nourish your plants – they provide nutrients in a readily available form, so they’re quickly absorbed by plants’ roots.
You can buy chemical fertilisers at the garden centre, but by making your own using comfrey leaves, you’ll have a steady supply of organic, nutrient-rich feed for free.
Comfrey has very deep roots, which means it extracts large quantities of nutrients from far below the soil’s surface, inaccessible to other plants. These nutrients are stored in its leaves. By harvesting the leaves and letting them break down, you’ll have a rich, dark, nutrient-rich plant food to use around the garden. It’s especially rich in potassium, making it the ideal feed to promote flowers and fruits in a range of plants, including tomatoes.
Watch Monty Don explain how to make a liquid comfrey feed in his video, below: Green Video Post Element Video ID: “b256417b678981002e603ccd876e0d554bcafff0” Mix ID: “” Player ID: “qAUyOzk5” If the player doesnt appear here within a few seconds, the Player ID or Licence Key (set via IM Green Suite settings) might be invalid.
Comfrey tea is an organic fertilizer that can provide excellent nutrition for plants, especially flowering and fruiting varieties. It contains high levels of potassium, nitrogen and phosphorus which are necessary for productive plants. However, comfrey tea needs to be diluted properly before using it on plants. This article explains how to dilute comfrey tea to get the maximum benefits.
What is Comfrey Tea?
Comfrey tea is made by steeping comfrey leaves in water This allows the nutrients in the leaves to be extracted into the water, creating a concentrated liquid fertilizer
The most common method is to fill a container with freshly cut comfrey leaves, add water just to cover the leaves, and allow it to steep for 2-6 weeks This produces a dark, concentrated “tea” that needs to be diluted significantly before using on plants
Another method is to layer chopped leaves and water in a container, without fully submerging the leaves This aerobic process produces a lighter tea in 1-2 weeks
Either way, the finished comfrey tea is packed with essential nutrients that plants need – potassium for fruit production, nitrogen for healthy growth, and phosphorus for root and flower development. But it needs diluting for safe usage.
Why Dilute Comfrey Tea?
While the nutrients in comfrey tea are beneficial for plants, the tea is too strong to use undiluted. Applying pure comfrey tea can damage or even kill plants.
Some key reasons you need to dilute comfrey tea before using it:
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It has a very high nutrient concentration that can “burn” plants if used undiluted. Always test on a small area first.
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The decomposing leaves alter the pH making the tea acidic. Diluting buffers the pH for plant safety.
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Undiluted comfrey tea may contain toxins from certain comfrey species that can be harmful in large concentrations.
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Some additional bacteria or mold can grow on the leaves during steeping. Diluting minimizes any potential issues from microbes.
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It has a strong odor that will be less noticeable when mixed into water.
Diluting comfrey tea moderates the nutrient levels and creates a safe, beneficial fertilizer for your garden plants.
How Much to Dilute Comfrey Tea
Most recommendations are to dilute comfrey tea at a ratio of 1 part comfrey tea to 10 parts water. However, the exact dilution rate depends on the concentration of your finished tea.
Stronger concentration:
- Dilute at a 1:15 or 1:20 ratio if your tea is very dark brown or black.
Medium concentration:
- Dilute at 1:10 to 1:15 if your tea is medium to dark brown.
Lighter concentration:
- You may only need a 1:5 dilution if your tea is lighter brown.
The more you dilute the tea, the more applications your batch will cover but the less nutrients each application will provide. Find the right balance for your needs.
A good rule of thumb is to start with a 1:10 dilution and adjust from there if needed. It’s easier to increase concentration than deal with burned plants from too strong a mix!
How to Dilute Comfrey Tea
Follow these simple steps for diluting your finished comfrey tea before using it in the garden:
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Assess the concentration – Check the color and thickness of your finished tea to estimate the ideal dilution rate, as explained above.
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Get two containers – You’ll need one container for measuring out the concentrated tea and another larger container for diluting it. Use watering cans, buckets, or jugs.
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Add tea and water – Add 1 part comfrey tea to at least 10 parts water. Adjust as needed based on concentration. If using a watering can, fill it 10% full with tea then top up with water.
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Stir well – Mix the tea and water thoroughly so the nutrients distribute evenly.
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Test pH – Check that the pH is between 6-7, neutral enough for plant usage. Add a bit of lime if too acidic.
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Label – Mark the container with the dilution rate for reference.
Your nutritious, plant-safe comfrey fertilizer is ready to use!
How to Apply Diluted Comfrey Tea
Only apply diluted comfrey tea directly to the soil around your plants. Using it as a foliar spray risks leaf burn.
Here are some tips for getting the most benefits:
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Water it into the soil around the root zone of each plant, not just sprinkled on the soil surface.
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Focus on heavy feeding plants – tomatoes, peppers, eggplants, berries, fruit trees.
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Apply it every 1-2 weeks throughout the growing season for continuous nutrition.
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Alternate comfrey tea with compost tea or manure tea for a diversity of nutrients.
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Use higher rates when plants are flowering and fruiting to boost production.
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Adjust frequency based on plant response – less if seeing burned tips, more if plants are still hungry.
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Stop feeding comfrey tea 2-3 weeks before harvesting fruits and vegetables.
With the right dilution and application, comfrey tea can be an amazing boost for your garden plants. Adjust strength as needed to optimize benefits in your soil and climate.
Common Questions about Diluting and Using Comfrey Tea
Here are answers to some frequently asked questions about preparing and applying diluted comfrey tea:
How long does diluted comfrey tea last?
Diluted tea should be used within 24 hours for maximum nutrient effectiveness. The nitrogen starts degrading quickly after dilution.
Can the unused tea be stored after diluting?
It’s best to only dilute what you will use right away. But you can store diluted tea up to 1 week in the refrigerator in an airtight container.
What is the ideal water temperature for dilution?
Lukewarm water, around 60-75°F, is ideal. Too hot will degrade nutrients faster. Too cold won’t properly dissolve the tea.
Can I use hard or soft water to dilute it?
Either works fine. Hard water may leave mineral residue but won’t affect nutrient content.
Is rainwater or tap water better for diluting?
Rainwater is slightly preferable as it has no chlorine or chemicals, but tap water works fine too.
How often should I apply the diluted tea?
Every 1-2 weeks is ideal for most plants during the growing season. Adjust as needed based on plant response.
Should I alternate comfrey tea with other fertilizers?
Yes, alternate with compost tea, manure tea, fish fertilizer, etc. for a diversity of nutrients over the season.
Can I use diluted comfrey tea for container plants?
Yes, it works great for containers! Use a milder dilution and feed more carefully to avoid buildup in pots.
Troubleshooting Issues with Comfrey Tea
If you notice any problems after applying diluted comfrey tea, here are some potential causes and solutions:
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Burned leaf tips: Tea is too concentrated, dilute more before next use.
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Poor fruiting: Plants need more phosphorus, supplement with bone meal.
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Stunted growth: Nitrogen levels too high, reduce tea strength or frequency.
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Smell persists: Did not dilute enough, increase water ratio.
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Mold in tea: Do not use old tea, make a fresh batch.
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Low nutrient levels: Diluted too much, gradually increase tea concentration.
Adjust your dilution rate, application frequency, and timing to find the ideal comfrey tea regimen for your garden needs.
Conclusion
While comfrey tea has excellent potential to nourish your plants, proper dilution is essential before using it in your garden. Follow the guidelines in this article to modulate the potency for safe usage. Test on small areas first to dial in the ideal strength and application schedule. With careful dilution and application, comfrey tea can be an invaluable organic fertilizer for flourishing flowers and fruiting plants!
Step 1[image id=”29915″ size=”landscape_thumbnail” align=”none” title=”Harvesting comfrey leaves” alt=”Harvesting comfrey leaves” classes=””] Harvesting comfrey leaves
Harvest comfrey leaves from the base of established plants. The hairy leaves can irritate the skin, so wear gloves if necessary.
Harvest Your Comfrey
Comfrey dies back in autumn and begins to re-emerge round about the start of April. By mid-May it’s probably looking like this:
Opinions differ as to whether or not to chop the entire plant off a couple of inches above ground (the fastest method) or to cut individual leaves. I prefer the latter, taking the largest leaves and leaving around a third of the smaller leaves to aid re-growth. I also leave any flowers or flower buds on the plant – bees love ’em – but you can remove the flowers to make more energy available for leaf production if you prefer.