The Complete Container Gardening Guide

Planting in containers, pots, or hanging baskets is an excellent way to add a touch of excitement to your home. It’s the perfect solution for small spaces, and a great creative project to keep winter interesting when you can’t get in the garden. Herbs, vegetables, flowers, palms and more, there are endless options for what you could grow!

Whether you’re leaning towards something fun or minimalist, there are all kinds of containers you can use for growing small and large plants. Beyond purpose-built gardening pots, your container plants can sit inside old household items, such as kettles, cups, cooking pots, and anything else you can find.

Let’s explore a few key steps to ensure your container-potted plants see success!

Choosing a container

There are no hard and fast rules for choosing the right container for planting, but here are some things to keep in mind:

Larger pots are easier to care for because they’re less prone to drying out, as the soil retains more moisture.

Large pots allow you to plant more than one species of plant, creating variety.

Consider the weight if you plan to move them around, and opt for something lighter if you’re a rearranger.

Smaller pots are great for filling in areas like windowsills, small decks and other areas with limited space.

Pots with a narrow base are prone to toppling over if not supported properly.

Pots with a narrow neck will cause re-potting issues, and you may have to sacrifice the pot.

What potting mix to use

For successful container gardening, it’s essential to use the best mix you can afford, as this will provide nutrients to your plants, promoting healthy growth and development. Consider the following:

If you’re planting vegetables or herbs, use specifically blended potting mixes for fruiting plants, such as citrus dwarf fruit trees, tomatoes and strawberries.

Palms and flowers require a mix that has long-term fertiliser added. The bag will state (in months) how long the fertiliser will last.

Regular watering is key to successful plant growth.

Choosing a mix that has an added wetting agent, such as Saturaid, helps greatly.

Saturaid can be added to existing pots that have become too dry.

Choosing plants

This is the area where your taste and style can shine. You can grow anything in containers, so don’t be afraid to experiment with some new ideas, whether fruit, veg, herbs or flowers. Plants are never wasted, and if they don’t work out the way you planned, you can always put them in the garden soil. When choosing plants to be grown in containers, keep this in mind:

For container plants to thrive, they require the same conditions as those in the ground.

Work with what you’ve got: if you have a very sunny deck or patio, choose plants that thrive in the sun.

Herbs make great container plants; mix them with flowering bulbs for a pop of colour and texture.

Achieve a cohesive look by using a colour wheel to match colours.

Use lighter foliage to lighten up a dark area.

Use annuals to fill holes in more permanent plantings.

Try to avoid plants that grow quickly, as they can be hard to control and will soon outgrow their pots.

Imagine how tall the plant will eventually be; will it balance the size of the pot?

Container gardening involves providing plants with compatible, healthy soil conditions. Plants that prefer acid-rich soils might not suit the garden, but they can thrive in a container with specific soil conditions.

How to feed

A potting mix with fertiliser will only last for the time stated on the bag, but plants still need their nutrients. Successful pot plants require frequent feeding and care:

If you’re keeping plants in the container, add some slow-release fertiliser after a season.

Scratch up the surface of the soil and add in the fertiliser, then top up the soil level.

Liquid fertilisers should be used on a regular basis, as they are the most effective way to provide your plants with the extra nutrients they need.

Mix up liquid fertilisers in a watering can and water them into the soil.

Note: All potting mixes can carry Legionnaires' disease, so it’s essential to follow the opening instructions on the bag. Follow these same precautions when using your stored potting mix.

How important is watering?

Soil in containers dries out easily, as these plants are more exposed to the sun. This becomes evident when you apply water, and it appears to pass straight through the soil and out of the drainage holes at the bottom. Here are some tips to help with your watering regime:

1. Water regularly and well, and give the soil a good soaking.
2. Check for moisture content by inserting your finger into the soil or gently scratching the surface.
3. Consider grouping your pots together, as this will make watering them easier.
4. Using pebbles for a decorative effect will also act as protective mulch and help to conserve and retain water.
5. Use Saturaid by scratching it into the top layer and watering it in well.
6. Potting mix will settle, so ensure there is a minimum 50mm gap from the soil to the top of the pot to prevent water from flowing over the top when you water.

Top tips for successful container planting

7. 1. Drainage is important in pots, so check that you have enough. A container with insufficient holes will retain water and waterlog your plants. Plastic or wooden containers let you make more holes, which improves drainage.
8. 2. Other types of pots may require using bits of broken pots or rubble to help with drainage.
9. 3. If you’re placing your containers on a wooden deck, use pot feet to raise your pots up so they don’t mark the wood. Pot feet will also help with drainage.
10. 4. Slugs and snails like your plants wherever they are, so you’ll still need to protect your plants if they’re exposed outside.
11. 5. When reusing old pots, give them a thorough wash with bleach to prevent the transfer of pests or diseases.
12. 6. Potting mixes have a use-by date. Old, dry and dusty mix won’t benefit your new plants, so always use a fresh mix.
13. 7. Keep weeds out, as they will compete for food and water.
14. 8. Dividing plants is still necessary; this is a good time to freshen up the soil before you replant.
15. 9. If you’re going away, put your containers in the garden to give them some protection from the sun.
16. 10. If you’re spraying for bugs and diseases in the garden, do the same for your pots.

Buy pots, planters and more gardening gear at Trade Tested

Ready to kick off your container gardening project? Explore our range of quality pots and planters at Trade Tested. Or, take your project to the next level with our wine barrels and grow bags. Find everything you need to bring your balcony, patio or deck to life with fast, nationwide delivery. Get in touch with us for assistance.

Customer opinions

Lechuza Balconera Planter

“Really neat planters. Have them on my terrace growing herbs. Just perfect for that. Super excellent watering system too. If I go away for a few days, I don’t have to worry!”

Lechuza Cubico Planter

“What an excellent product. I love that it came with a little bag of gravel and instructions I could follow. Lightweight and easy to fit together.”

Lechuza Cilindro Planter 3.3m

“Exceeds expectations, great price and great quality. A good weight that doesn't blow over in stormy weather. Highly recommended.”

Frequently asked questions

How to make a container garden step by step for beginners

1. 1.Select your plants: Decide whether you want to grow evergreen shrubs, fruit trees, potatoes, spinach, flowering bulbs or other greenery. It pays to choose plants that have similar water and sunlight needs!
2. 2. Choose your containers: Select pots that are appropriately sized and designed to drain water with enough holes at the bottom.
3. 3. Add potting mix to your containers: Use a high-quality, free-draining potting mix. Hydrophobic potting mixes don’t absorb water deeply and require a wetting agent.
4. 4. Arrange your existing plants, seeds or seedlings: Place the largest plant in the centre or back, fillers around it, and trailers near the edges.
5. 5. Plant: Gently firm the soil and remove air pockets. Then, sow seeds into the mixture following the recommended depth, or place existing loosened plants into the centre of the pot, securing them with more potting mix.
6. 6. Water: Water your new potted plants thoroughly until they drain from the bottom.
7. 7. Maintain regularly: Feed your plants with slow-release fertiliser, water when the soil dries out, and keep them under control by trimming back overgrowth.

What is the rule of thumb for container gardening?

Good rules of thumb for container gardening include:

Matching the right plant to the right pot; choose a container that’s large enough for the plant’s root system and has proper drainage holes to prevent waterlogging.

Using high-quality potting mix rather than garden soil, and ensuring plants receive the right amount of sunlight and suitable, regular watering for their species.

Following “thriller, filler, spiller”, which involves growing one tall central plant, one medium plant to fill space, and one trailing plant to spill over the edges.

What is the most common mistake made with container plants?

Some examples of common mistakes made with container plants are:

Improper watering; many people water either too much or too little. Overwatering can suffocate roots and cause rot, so always check the soil moisture before re-watering and keep in mind the top few centimetres should be dry.

Choosing pots that are too small or without drainage holes.

Using soil instead of the appropriate potting mix.

Placing sun-loving plants in shady spots.

How many plants should you put in a container?

It depends on the size of the container and the growth habit of the plants. A 30cm pot can hold three to five small bedding plants, while a 40cm pot can host up to nine. The key is to allow each plant enough room for roots to expand, avoid overcrowding, as this restricts growth and increases competition for nutrients and water. You also need to make sure you aren’t pairing incompatible plants in the same pot.

What grows best in a container garden?

In New Zealand, container gardens thrive with both edible and ornamental plants. Easy edible options include basil, parsley, mint, rocket, lettuce, cherry tomatoes, strawberries, and dwarf citrus trees. For decorative pots, consider using shrubs, petunias, geraniums, begonias, lavender, succulents, or native grasses like Carex. Choose plants suited to your region’s conditions, like succulents and geraniums for dry areas, or ferns and impatiens for shaded, damp spots.