Make Your Own Garden Feeds and Sprays
Turn your scraps, weeds, manure and compost into free feeds, plus honest, bee-safe sprays for the home garden
Some of the best garden inputs are free, and you already make them. Kitchen scraps, lawn clippings, weeds, animal manure and finished compost can all become liquid feeds that grow strong, productive plants. A few simple sprays made from soap, milk or oil will help you handle common pests and diseases without reaching for harsh chemicals.
This is the heart of a working homestead. Your outputs become your inputs. The chickens make manure, the worms make castings, the compost bin turns scraps into black gold, and all of it feeds the garden that feeds you back. See how every part connects in Connections, and learn the soil side in our composting guide.
Homemade Fertilisers and Feeds
Liquid feeds are quick to make and gentle on plants when diluted properly. The golden rule for nearly all of them is the same: dilute until the liquid is the colour of weak tea, then water it onto moist soil around the plant, not onto bone-dry ground. A light feed every week or two beats a heavy feed now and then.
Compost tea
A gentle, all-round feed that spreads a little finished compost a long way. There are two ways to make it.
- Simple steep: put a shovel or two of mature compost in a hessian sack or old pillowcase, drop it in a bucket or drum of water, and let it steep for 1 to 2 days, stirring now and then. Lift the bag out and use the liquid.
- Aerated brew: bubble air through the mix with an aquarium pump for 24 to 36 hours, often with a spoon of unsulphured molasses to feed the microbes. This grows more living organisms but needs to be used the same day.
Dilute to the colour of weak tea. Use fresh, ideally the day you finish it, and water it onto the soil. Do not store it, as it goes anaerobic and sour.
Worm castings tea and worm wee
If you run a worm farm you have two of the best free feeds going. Worm castings tea is made by steeping a couple of handfuls of castings in a bucket of water for a day, then watering it on diluted to weak tea colour. The liquid that drains from the bottom of a worm farm, often called worm wee, is usually quite concentrated.
Dilute the worm farm liquid heavily, around one part liquid to ten parts water, until it is the colour of weak tea, before you use it. Use every week or two through the growing season.
Comfrey or nettle feed
Comfrey leaves are rich in potassium, which makes this one of the best free feeds for flowering and fruiting plants like tomatoes. Nettle is higher in nitrogen and better for leafy growth early in the season. The method is the same chop and steep.
- Chop a bucket of leaves, weigh them down with a brick, cover with water and put a lid on loosely.
- Leave for 2 to 4 weeks. It will smell strongly, so keep it away from the house and the neighbours.
- Strain off the dark liquid.
Dilute hard, roughly one part feed to ten parts water, until it is the colour of weak tea. Use weekly to fortnightly. The smell is the price of a free, high-potassium feed.
Manure tea
Aged manure from chickens, cows, horses or sheep makes a good general feed. Use well-rotted manure, never fresh, as fresh manure is too strong and can carry pathogens.
Put aged manure in a hessian sack, suspend it in a drum of water and steep for a few days. Dilute the result to weak tea colour. Use on the soil around plants, not on the leaves of anything you eat raw, and water it in.
Banana peels, wood ash and epsom salts
These get talked up more than they deserve, so here is the honest version.
- Banana peels contain some potassium, but soaking them in water gives only a weak feed. They are better chopped into the compost or a planting hole. Treat them as a small bonus, not a main feed.
- Wood ash from untreated wood adds potassium and lime, so it raises soil pH. Use it sparingly, a light scatter worked into the soil, and not around acid-loving plants like blueberries. Keep it dry until you use it.
- Epsom salts are magnesium sulfate. They only help when a plant is genuinely short of magnesium, shown as yellowing between the veins of older leaves. A foliar spray of one tablespoon per litre of water can green it up. They are not a general fertiliser, so do not use them as one.
Seaweed solution
Seaweed is a tonic more than a fertiliser. It is low in the main nutrients but rich in trace elements and natural growth stimulants that help with rooting, transplant shock and general resilience. You can buy concentrate, or steep rinsed fresh seaweed in water for a few weeks where it is legal to collect it.
Dilute to weak tea colour and use as a soil drench or a light foliar feed every week or two. It pairs well with a richer feed like comfrey rather than replacing it.
Homemade Sprays
Homemade sprays are useful tools, not silver bullets. They work best as part of a calm, observant approach: identify the problem first, encourage the predators that do your pest control for free, and only spray when you really need to. Read more on that approach in our pest and disease guide.
Insecticidal soap
The most effective homemade spray for soft-bodied pests like aphids, mites and whitefly. It works by contact, so it only hits what you spray.
Make it with one to two teaspoons of pure soap, such as a pure liquid castile soap or grated pure soap flakes, dissolved in one litre of water. Do not use dishwashing detergent, which contains degreasers that burn leaves.
Use by spraying directly onto the pests, including the undersides of leaves, in the evening. Repeat every few days while the pest is active. Test first on a few leaves.
Neem oil
Neem is a plant oil that disrupts the feeding and breeding of many pests and helps with some fungal issues. Mix neem oil with a little pure soap as an emulsifier and water, following the product rate on the label, and shake well.
Garlic and chilli spray
A deterrent, not a cure. The smell and heat make leaves less appealing to some chewing and sucking pests, but it will not wipe out an infestation.
Make it by blending a few cloves of garlic and a hot chilli or two with water, steeping overnight, straining well, then diluting into a litre of water with a drop of pure soap to help it stick. Use as a deterrent on foliage, reapplying after rain. Wear gloves and keep it away from your eyes.
Milk spray for powdery mildew
A genuinely useful spray for powdery mildew on cucurbits, beans and the like. Diluted milk appears to disrupt the fungus on the leaf surface.
Make it at about one part milk to nine parts water. Use as a preventive or at the first white patches, spraying both sides of the leaves in the morning so they dry through the day. Repeat weekly.
Bicarb spray for fungal issues
A weak solution of bicarbonate of soda raises the leaf surface pH and can slow fungal diseases like powdery mildew and black spot.
Make it with one teaspoon of bicarb soda and a few drops of pure soap in one litre of water. Use sparingly and not in hot sun.
What to Use for What
A quick reference. Always dilute feeds to weak tea colour, water onto moist soil, and spray in the evening away from flowers and bees.
| Your goal | Homemade option | How often |
|---|---|---|
| General all-round feed | Compost tea or worm castings tea | Weekly to fortnightly |
| Boost flowering and fruiting | Comfrey feed (high potassium) | Weekly to fortnightly |
| Push early leafy growth | Nettle feed or aged manure tea | Fortnightly in spring |
| Tonic for trace elements and stress | Seaweed solution | Weekly to fortnightly |
| Fix magnesium deficiency only | Epsom salts foliar spray | Once, then check |
| Aphids, mites, whitefly | Insecticidal soap (pure soap) | Every few days while active |
| Powdery mildew | Milk spray, 1 part milk to 9 water | Weekly, evening |
| Fungal spots, mildew | Weak bicarb spray | Sparingly, not in sun |
| Deter chewing and sucking pests | Garlic and chilli spray (deterrent) | Reapply after rain |
The Homestead Loop in Action
This is where the pieces join up. Your kitchen scraps and garden waste feed the compost bin and worm farm. Those turn into compost, castings and liquid feeds. Comfrey and nettles grow in a corner and become a free potassium feed. The garden grows the harvest, and a glut becomes a stocked pantry through preserving. Nothing leaves the system that does not have to. See the whole picture in Connections.
Track Your Feeding and Spraying
The Planting Season app remembers what you fed and sprayed, when, and what worked, and ties your compost and worm outputs back to the beds they feed.
Open the App →Frequently Asked Questions
Is compost tea worth making?
Compost tea is a gentle, free liquid feed and a good way to spread the benefit of a small amount of finished compost across many plants. It will not replace feeding the soil with actual compost and mulch, and the science on disease suppression is mixed, so treat it as a useful top-up rather than a miracle. Use it fresh, diluted to the colour of weak tea, and water it onto the soil around your plants.
Do banana peels actually feed plants?
Banana peels do contain potassium, but the amount released is modest and slow. They are fine added to the compost or chopped into a planting hole, but soaking peels in water makes a very weak feed. For a real potassium boost for fruiting plants, comfrey or a seaweed solution does far more. Treat banana peels as a small bonus, not a main feed.
What is the best homemade spray for aphids?
A simple insecticidal soap spray is the most effective homemade option for aphids. Mix one to two teaspoons of pure soap, not detergent, into a litre of water and spray it directly onto the aphids, including under the leaves, in the cool of the evening. It only works on contact, so repeat every few days as needed. A strong jet of water also knocks many aphids off, and ladybirds will clean up the rest.
Are homemade sprays safe for bees?
Homemade sprays can still harm bees and other pollinators, so treat them with respect. Never spray open flowers, and spray in the evening when bees have stopped foraging so the spray can dry before they return. Insecticidal soap, neem and oil sprays can all kill bees on direct contact, so keep them off blooms entirely. Milk and bicarb fungal sprays are the gentlest on pollinators.
How often should I feed with a homemade liquid feed?
Most homemade liquid feeds suit a weekly to fortnightly schedule through the growing season, applied to moist soil. Diluted to weak tea colour they are gentle, so a light, regular feed beats an occasional strong one. Ease off as plants slow down in autumn and winter. Plants in pots need feeding more often than those in the ground because nutrients wash out faster.
Can I use dish detergent instead of soap for sprays?
No. Dishwashing detergents contain degreasers and additives that can burn leaves and are not the same as a pure soap. Use a plain pure soap, such as a pure liquid castile soap or grated pure soap flakes dissolved in water. Always test any spray on a few leaves first and wait a day to check for burning before treating the whole plant.
See also: Composting Guide and Fertilising Guide