Last updated on April 6th, 2022
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This is the season for seedlings. Now is the time for germinating them in your home or greenhouse, which of course requires good seed compost. The problem is most compost types (including multipurpose compost) you can buy from garden centres and nurseries are not ideal seed starting mixes. You have probably had some plants that no matter what you did, just did not germinate. They seemed overly watered on top but dry to the bones down below.
The cause? If the compost mixture isn’t right, it can lead to bad water absorption, something that proves fatal to your new seeds because they can rot before they start. If the nutrient content is wrong, it will hinder root growth and seedlings need very little nutrient value at first.
Plus, it’s expensive. No matter where you look, high-quality compost is expensive.
To that end, knowing how to make seed compost for starting seeds can prove very useful, especially if you are going to germinate from seed, season after season.
The perfect recipe for germinating seeds
To make anything, you need the perfect recipe. The seed starting mix needs to be low in nutrients, hold onto moisture without becoming soggy, and it needs to be light and fluffy so the roots can penetrate and spread without much resistance.
Getting the base mix right
Start with the base of your mixture should contain two parts of compost. When reading this compost mix, be advised that the parts are based on volume, so whatever amount you are making, you can keep to the same volume and ratio. We recommend just using a large jug to scoop the correct amounts in equal volumes.
Use 2 parts compost that has been sieved with a riddle
Compost will release nutrients slowly, something the growing seeds need. Break apart the compost with your hands, but we do recommend using a compost riddle to make it as fine as possible.
Mix the compost with 2 parts coir
Mix in two parts coir, or coconut fibre. This is what often lines store-bought wireframes for hanging baskets and it is a great alternative to peat moss, and we are always trying to find good alternatives to peat to do our part to help the environment. While peat moss is the normal additive here, it is not a sustainable product to use while coir is, which is why we recommend it.
If you order coir and it arrives in a block form, you need to rehydrate it in a bucket of water until it breaks apart.
- High quality, cleaned and pre-treated coco coir ideal for pot culture or other bulk uses
- Very easy-to-use and gives great results
- A pure, organic product with a homogeneous structure and has had a full buffering, eliminating the side effects of growing on coir
- Free of harmful viruses and soil diseases, thanks to CANNA's unique production process
- Complex water/air system that that provides the ideal conditions for growing plants
Finally, add one part of perlite to the mix
Lastly, add one part of perlite to improve air content and lighten the mixture. Sand is an alternative to perlite, but it will produce a heavier mix.
- PLANT!T Perlite can be used for soil conditioning – increasing aeration and drainage in heavy, hard to manage soils
- Repairing/laying down lawns – PLANT!T Perlite gives additional aeration and drainage when raked into spiked holes
- Planting trees and shrubs – loosens and aerates soil to encourage root development
- A natural, pH neutral and sterile growing medium derived from volcanic rock
- Aid nutrient uptake and improves plant health and growth. Available in 10L and 100L bags
Mixing the compost mix
When you have all your ingredients, you need to mix them thoroughly. Use your hands for better tactile engagement and thoroughness; the more consistently mixed the better. When you are done, store your mix in a lidded container or thick plastic sack in a cool, dry place.
Germinating seedlings
When it comes time to use your homemade seed mix, moisten it so that it is not too sodden, but not too dry either. Use recycled containers, seed trays, or module trays and gently press down on the mixture as you fill your container of choice. Consider using a heated propagator to improve the germination rate and speed up the process.
- 52 cm heated propagator
- Non thermostatic - simple on-off control via mains
- Clear cover with adjustable ventilation
- Adjustable ventilation panels for humidity and air temperature control
- Sealed unit with an economical 22 W heater - insulated to retain heat within the propagator
Be sure to sow the seeds according to your packet instructions and water afterwards. Rest assured this mixture can be used as you transplant young seedlings and is something you can make year after year.
Would you rather buy seed compost?
- 𝗡𝗨𝗧𝗥𝗜𝗘𝗡𝗧-𝗥𝗜𝗖𝗛 𝗖𝗢𝗠𝗣𝗢𝗦𝗧 𝗙𝗢𝗥 𝗔𝗟𝗟-𝗣𝗨𝗥𝗣𝗢𝗦𝗘 𝗚𝗔𝗥𝗗𝗘𝗡𝗜𝗡𝗚: Formulated with organic, nutrient-rich materials, this seedling compost provides essential nutrients for robust plant growth. Ideal for indoor and outdoor plants, it supports everything from seed germination to mature plants in pots, tubs, and garden beds.
- 𝗢𝗣𝗧𝗜𝗠𝗜𝗦𝗘𝗗 𝗙𝗢𝗥 𝗦𝗘𝗘𝗗𝗟𝗜𝗡𝗚𝗦 & 𝗣𝗟𝗔𝗡𝗧 𝗦𝗧𝗔𝗥𝗧𝗦: Specially crafted for starting seedlings, this seed compost promotes excellent root growth and germination. It ensures proper drainage and moisture retention, giving young plants the perfect environment to thrive without risking overwatering.
- 𝗩𝗘𝗥𝗦𝗔𝗧𝗜𝗟𝗘 𝗠𝗨𝗟𝗧𝗜-𝗣𝗨𝗥𝗣𝗢𝗦𝗘 𝗨𝗦𝗘: This potting compost for seeds suits a variety of plants, including vegetables, fruits, flowers, herbs, and shrubs. Whether growing indoor houseplants, propagating cuttings, or improving outdoor garden soil, it’s a reliable solution for every gardening need.
- 𝗦𝗧𝗔𝗬 𝗠𝗢𝗜𝗦𝗧𝗨𝗥𝗘-𝗥𝗘𝗧𝗘𝗡𝗧𝗜𝗩𝗘 𝗪𝗜𝗧𝗛 𝗘𝗔𝗦𝗬 𝗗𝗥𝗔𝗜𝗡𝗔𝗚𝗘: Engineered to retain moisture while providing proper drainage, this seed and cutting compost balances water levels for healthier roots. It minimises overwatering risks and helps plants flourish even during dry spells, ensuring consistent hydration.
- 𝗚𝗘𝗡𝗘𝗥𝗢𝗨𝗦 𝟯𝟱-𝗟𝗜𝗧𝗥𝗘 𝗕𝗔𝗚 𝗙𝗢𝗥 𝗛𝗔𝗦𝗦𝗟𝗘-𝗙𝗥𝗘𝗘 𝗚𝗔𝗥𝗗𝗘𝗡𝗜𝗡𝗚: Supplied in a compact yet plentiful 35L bag, this cutting compost is easy to handle and store. Whether cultivating an indoor oasis or rejuvenating outdoor spaces, this compost offers the perfect quantity for your projects.
- For fast, healthy seed germination
- Feeds for the first 3 weeks
- Added vermiculite to retain moisture
- Peat Free
- Peat-Free Coir-Based Compost: Specially formulated to support seed germination and promote strong root development for healthy plants.
- Nutrient-Rich Formula: Contains slow-release nutrients and seaweed, providing the perfect balance of feed from germination to seedling stage.
- Moisture Retention: Designed to retain moisture, ensuring your seeds have the optimal environment for growth.
- Eco-Friendly Packaging: Supplied in a biodegradable bag, which is also perfect for adding water directly to the compost.
- Ideal for All Seeds: Perfect for giving your seeds the best start, whether you're growing vegetables, flowers, or herbs.
- Westland Gro-Sure Seed & Cutting Compost Bale - 20L
- Product type: SOIL
- Brand: Gro-Sure
Last update on 2025-02-10 / Affiliate links / Images from Amazon Product Advertising API
