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How to Sow and Grow

These instructions are for anyone interested in growing plants, whether you are a beginner, or a more experienced gardener, you should find some useful tips and advice below.

Dont forget to watch the YouTube videos at the end of each section.

  1. Planting seeds

 

Equipment:

  • Seeds

  • Seed tray or module, seed compost or coir pellets

  • Sieve or colander

  • Labels and indelible pen

  • Glass, plastic or clingfilm to cover

  • Watering can

  • Warm place for seeds to germinate

 

  1. Fill seed tray or modules with moist compost to the brim, ensuring that all corners are filled.
  2. Gently firm compost with another tray or a block of wood, to give a flat surface to sow on, leaving a small gap from the top of the tray (around 10mm).

  3. Gently water the tray or modules and allow excess to drain away.

  4. If using coir pellets, soak them in a bucket or the sink for 10 minutes until they expand.

  5. Sow seed thinly, leaving space around each seed. Use finger and thumb to gently scatter seed from the packet.

  6. Cover the seed lightly by sieving seed compost or vermiculite over the top - usually no more than the depth of the seed.

  7. If not watered before planting, water with a gentle spray - an upside down rose helps to create a finer spray. Too heavy a spray and you will disturb the seed.

  8. Label the container with the name of the seed.

  9. Cover the container with clear glass, plastic or cling film.

  10. Place tray/modules in a warm spot to germinate such as a windowsill, propagator or greenhouse.

  11. Check daily for emerging seedlings. Once germination occurs, the glass, plastic or propagator lid should be removed to increase ventilation.

  12. Keep the compost just moist at all times to maintain steady growth until the seedlings can be pricked out (transplanted) to bigger pots.

 

https://www.youtube.com/watch?v=Jeqnds6RfK4

Courtesy Suttons Seeds

  2. Pricking out/potting on plug plants

 

Equipment

  • Seeds

  • Potting compost

  • Seedlings/plug plants

  • Dibber, pencil or stick

  • Labels and indelible pen

  • Watering can

  • Warm place for plants to grow on

 

  1. Fill the pots with compost.

  2. Lightly water the post and allow to drain.

  3. Remove the plug or seedling gently from the tray- you may need to poke a pencil up through the hole in the base to loosen it and/or use a blunt stick or dibber to loosen the compost. Lift the seedlings by holding one of the true leaves (not the first seed leaves produced just after germination) between finger and thumb. Try to keep as much compost around the roots as possible.

  4. Use the dibber to make a larger hole for the seedling in its new pot of compost and place the plant in it. Firm the plant in.

  5. Label !

  6. If the seedlings are leggy, bury them slightly deeper (up to the first pair of leaves) in their new pot

  7. Keep well-watered. Use a fine rose at first so as not to flood the plants.

  8. Feed pricked-out seedlings and plug plants with a liquid fertilizer around every two weeks in most cases.

  9. If ornamental seedlings become lanky, pinch out their growing tips to encourage branching. If necessary, several pinchings can be done. Avoid legginess by growing plants in bright light and avoiding overly warm conditions.

  10. Damping off, when seedlings collapse and decay, can happen in spring when light levels and temperatures are low, and seedlings grow slowly. Remove any collapsed foliage or seedlings. Don’t over-water. Keep seedlings well ventilated to reduce humidity. Use clean seed trays and pots.

  11. As plants develop, they may show signs of stress: dull foliage, if short of water or pale lower leaves may suggest a lack of fertilizer.

  12. Young plants grown from seed or plugs often benefit from being hardened off when the weather improves. If growing in a greenhouse, start leaving doors and windows open during the day and close them at night. If you have a cold frame, move plants into it with the lid open slightly during the days of the first week and closed at night. Gradually raise the lid during the next fortnight until removing it entirely. Otherwise put plants in a sheltered position (in front of a south-facing wall or hedge is ideal) during the day and cover with two layers of fleece to prevent sun scorch and temperature shock. Bring indoors at night. Gradually remove fleece during the day and, eventually leave outside at night, covering only if frost is expected.

 

https://www.youtube.com/watch?v=N12JBC41CPA

Courtesy Deco Bliss

  3. Dividing plants

 

Equipment

  • Pots

  • Potting compost

  • Seedlings/plug plants

  • Dibber, pencil or stick

  • Labels and indelible pen

  • Watering can

Most perennials benefit from division every two to three years to maintain health and vigour. For the purposes of propagation, the task can be done more regularly.

Plants can be divided successfully at almost any time if they are kept well-watered afterwards. However, division is most successful when the plants are not in active growth.

Divide summer-flowering plants in spring (Mar-May) or autumn (Sep-Nov) when the soil is dry enough to work. Spring is also better suited to plants that are a touch tender.

Many spring-flowering plants, such as irises, are best divided in summer (Jun-Aug) after flowering when they produce new roots.

  1. Lift plants gently with a garden fork, working outwards from the crown’s centre to limit root damage. Shake off excess soil so that roots are clearly visible

  2. Some plants, such as Ajuga (bugle), produce individual plantlets which can simply be teased out and replanted

  3. Small, fibrous-rooted plants such as Heuchera, Hosta and Epimedium can be lifted and pulled apart gently. This should produce small clumps for replanting

  4. Large, fibrous-rooted perennials, such as Hemerocallis (daylily), require two garden forks inserted into the crown back-to-back. Use these as levers to loosen and break the root mass into two sections. Further division can then take place

  5. In some cases, a sharp knife, axe or lawn edging iron may be needed to cleave the clump in two

  6. Plants with woody crowns (e.g. Helleborus) or fleshy roots (e.g. Delphinium) require cutting with a spade or knife. Aim to produce clumps containing three to five healthy shoots

  7. Plant divisions as soon as possible and water them in well. Alternatively, pot up individually to build up size, overwintering pots in a frost-free environment.

https://www.youtube.com/watch?v=Un5JvyzpBYE

Courtesy Alan Titchmarsh and Waitrose

  4. Hardwood cuttings

Most deciduous shrubs and many climbers can be propagated by hardwood cuttings. Hardwood cutting are taken in the dormant season (mid-autumn until late winter) after leaf fall. The ideal time is just after leaf fall or just before bud-burst in spring.

  1. Select vigorous healthy shoots that have grown in the current year

  2. Remove the soft tip growth

  3. Cut into sections 15-30cm (6in-1ft) long, cutting cleanly above a bud at the top, with a sloping cut to shed water and as a reminder which end is the top

  4. Cut straight across at the base below a bud or pair of buds and dip the lower cut end in a hormone rooting powder (this promotes root formation, it also contains a fungicide, protects against rotting). Cut through the ‘heel’ where the shoot joins a branch for shrubs with pithy stems such as Sambucus (elder)

  5. Insert cuttings into pots of gritty potting medium such as 50:50 coarse grit and multi-purpose compost. Keep the pots in a sheltered cold frame or unheated greenhouse until the following autumn, ensuring that they do not dry out.

 

https://www.youtube.com/watch?v=WAC2BqCUWQM

Courtesy Monty Don

  5. Softwood cuttings

 

Softwood cuttings are mostly used for propagating hardy and tender perennials and can also be used for a wide range of mainly deciduous shrubs. Most softwood cuttings are taken in spring and early summer, from the tender new growth of the season. If potted by mid-summer they will develop sufficient roots to survive the winter, otherwise pot up in the following spring.

  1. Collect material early in the day when it is full of water (turgid)

  2. Collect non-flowering shoots, as they will root more readily, or remove the bud before potting up

  3. Remove up to 10cm (4in) of shoot, cutting off the material neatly above a bud on the parent plant

  4. Place the cuttings material in a clean plastic bag with a label. Store the bag of material in the fridge if you cannot prepare the cuttings immediately

  5. Most softwood cuttings are nodal, i.e. cut at the bottom just below the leaf joint or node, where there is a concentration of hormones to stimulate root production.

  6. Using a sharp knife trim below a node to make a cutting about 5-10cm (2-4in) long

  7. Remove the lower leaves, pinch out the soft tip and dip the base of the cutting in hormone rooting powder or liquid

  8. Make a hole for the cutting in a container of cuttings compost using a dibber (a clean blunt stick) and insert the base of the cutting with the first pair of leaves just above the level of the compost

  9. Label the pot and water it from above to settle the compost

  10. Cover the pot with a plastic bag

  11. Cuttings should be placed in good light but not direct, scorching sunlight

  12. Ensure the compost is moist until the cuttings are well-rooted which takes about 6 to 10 weeks

https://www.youtube.com/watch?v=wD5PC9cmbhI

Courtesy English Gardening Magazine