How to Start Seeds in Recycled Cups and Containers
You do not need special equipment to start seeds. You do not need a greenhouse, a heated mat or expensive seedling trays. You can start a whole nursery of seedlings using containers that would otherwise end up in the bin.
At our garden in Soshanguve, we start most of our seedlings in used cups and food containers. Styrofoam cups, paper coffee cups, yogurt tubs, plastic food trays, they all work. The plants do not care what the container looks like. They only care that the soil is good, the container has drainage and there is enough room for the roots to grow.
This article walks through exactly how we do it, from collecting free containers to poking drainage holes and growing healthy seedlings on a budget. If you are growing bell peppers, I covered how to move them into the garden in a step-by-step guide to transplanting bell pepper seedlings.
In This Article
- Why recycled containers work for seedlings
- Collecting free containers
- Any food container can work
- Poking drainage holes
- The best soil mix for recycled pots
- Filling and planting
- Watering and light
- Feeding young seedlings
- When to transplant out of the container
- The DIY nursery on a budget
- What I learned from starting seeds in recycled containers
Why Recycled Containers Work for Seedlings
A seedling only needs a few things to grow. It needs enough soil for its roots, drainage to prevent waterlogging, light, water and a bit of warmth. A cup or a food container provides all of that.
The size of the container matters more than the material. As long as the container is at least 5 to 8cm deep, it will hold enough soil for a seedling to grow through the first few weeks. Anything larger works too, and may let the seedling stay in the pot longer before transplanting.
Using recycled containers saves money. Seedling trays bought new can cost more than the seeds themselves. When you start seeds in cups and yogurt tubs, the only thing you are spending is time and effort.
Collecting Free Containers
Containers are everywhere. Before you throw anything away, look at it and ask if it could hold soil.
Some of the containers we use most often:
- Styrofoam cups
- Paper coffee cups
- Yogurt tubs
- Plastic food trays
- Small takeaway containers
- Ice cream tubs
- Old plastic bottles cut in half
Rinse them out before use. You do not need to sterilise them. A quick wash with water is enough to remove any food residue that might attract pests or mould.
Do not worry about the branding on the container. A yellow McCafe cup with a McDonald's logo is just as good as a plain white one. The seedling does not care what the outside looks like.
Any Food Container Can Work
The best containers for seedlings are the ones you already have. Every time you finish a yogurt, a takeaway meal or a coffee, you are also finishing a potential seedling pot.
We have grown seedlings in almost every kind of food container you can imagine. Yogurt tubs, small plastic cups, ice cream containers and coffee cups all do the job. What matters is that the container is clean, has drainage and is deep enough for the seedling's roots.
Yogurt containers are particularly useful. They are usually deeper than coffee cups, they have a wider base and they are strong enough to be reused several times. The lid can even be used as a saucer underneath to catch water.
Poking Drainage Holes
This is the step that most people forget, and it is the step that matters most. Every container used for seedlings must have drainage holes in the bottom.
Without drainage, water collects at the bottom of the container. The soil stays wet, the roots are starved of oxygen and the seedling develops root rot. By the time you notice the problem, the seedling is usually already dead.
The holes do not need to be big. Three to five small holes in the bottom of the container are enough. You can make them with:
- A sharp knife or scissors
- A nail or a screwdriver
- A hot metal skewer (for plastic containers)
- A needle (for Styrofoam or paper cups)
Space the holes evenly around the base. If the container is plastic, press the hole through from the inside out so the edges do not catch water. If the container is paper or Styrofoam, a simple poke through is enough.
Test the drainage before planting. Fill the container with water and check that it runs out the bottom. If the water sits, the holes are too small or blocked.
The Best Soil Mix for Recycled Pots
Seedlings do best in a light, well-draining soil mix. Heavy garden soil compacts in small containers and does not drain well, which increases the risk of root rot.
Our mix for recycled pots is:
- 50% compost
- 30% coarse river sand
- 20% vermiculite or perlite
This mix holds moisture without staying wet, drains well and gives the seedling enough nutrients for the first few weeks. If you do not have vermiculite or perlite, you can substitute with more coarse sand.
We also mix in a small amount of chicken feather fertilizer for a slow-release nutrient source. A pinch per container is enough. Anything more can burn the seedling.
Filling and Planting
Once the container has drainage holes, fill it with the soil mix. Leave about 1cm of space at the top so that water does not overflow when you water.
Gently firm the soil down with your fingers. Do not pack it hard. You want the soil to be settled but still loose enough for roots to move through.
Plant the seed at the correct depth for its type. Most vegetable seeds go around 1cm deep. Small seeds, like lettuce, just need to be pressed into the surface. Larger seeds, like beans, go a little deeper.
Label the container. When you are starting several different crops at once, it is easy to lose track of which cup has which seed. A piece of masking tape on the side of the container works fine.
Watering and Light
Water gently after planting. A slow pour from a small cup or a spray bottle works well. Do not flood the container. The goal is to moisten the soil, not to wash the seed away.
Keep the containers in a spot with good light, but not direct midday sun. A windowsill, a shaded spot outdoors or a spot with morning sun and afternoon shade works well for most seedlings.
Check the soil moisture daily. Recycled containers dry out faster than garden soil because there is less soil volume to hold water. Water when the top of the soil feels dry to the touch.
Feeding Young Seedlings
Once the seedlings have their first set of true leaves, they can start receiving a light feed.
We use a fish liquid fertilizer diluted to half strength. This gives the seedling a gentle nitrogen boost without burning the roots. Full-strength feed is too strong for young seedlings and can damage them.
Feed once every 10 to 14 days while the seedling is still in the container. Once transplanted into the garden, the feeding schedule changes to the standard 14-day cycle.
When to Transplant Out of the Container
Seedlings started in recycled containers follow the same transplanting timeline as seedlings started in trays. Move them into the garden when they have their first set of true leaves and are strong enough to handle the change.
For some crops, this is around 3 to 4 weeks after germination. For others, it is longer. Peppers and tomatoes can stay in their containers a little longer. Lettuce and spring onions prefer to be moved sooner.
Before transplanting, water the container well. The soil will hold together better when it is moist, and the seedling will come out with the root ball intact.
The DIY Nursery on a Budget
The containers in the photograph above have all been used before. The McCafe cup started as a coffee. The Styrofoam cups came from a takeaway. The yogurt tubs came from breakfast. None of them cost anything.
That is the point of a DIY nursery. You do not need to buy anything special. You need soil, seeds, water, light and a bit of care. Everything else can come from what is already around you.
For gardeners on a tight budget, this approach opens up growing food to anyone. The cost of a packet of seeds and a bag of compost is often less than a single takeaway meal. Everything else, you can collect from your own kitchen.
What I Learned From Starting Seeds in Recycled Containers
Starting seeds in recycled containers taught me that gardening does not have to be expensive. It also taught me a few practical things along the way:
-
Drainage holes are not optional.
Every container needs them. Without drainage, seedlings die from root rot, and the whole point of starting them in a nursery is defeated. -
Any container works if it holds soil.
Cups, tubs, trays, bottles cut in half. If it is deep enough and has drainage, it can hold a seedling. -
Label everything.
When you are growing five different crops at once, you will forget what is in each container. Masking tape solves the problem. -
Water more often than you think.
Small containers dry out fast. Check the soil daily and water when the top feels dry. -
Feed gently.
Half-strength liquid fertilizer is enough for young seedlings. Full strength can burn the roots. -
Repurpose before you recycle.
Before throwing a container in the bin, ask if it could hold a seedling. The answer is usually yes.
Gardening Lesson
You can start a whole nursery from your kitchen waste.
Cups, yogurt tubs, coffee cups and food containers all work as seedling pots. Rinse them, poke drainage holes in the bottom, fill with a light soil mix and plant your seeds. That is all it takes to start growing your own food without spending money on equipment.
Soshanguve, Pretoria, South Africa
Growing Knowledge. Growing Food.