Growing Nasturtiums

Latest Update 27th July 2016.

  • I grow nasturtiums beneath my apple trees to help deter insect pests.
  • I also use the leaves fresh and uncooked.  They have a peppery sweet taste and I find them extremely helpful with digestion and acid reflux.
  • In Melbourne's warm temperate climate, they survive winters long enough for new plants to emerge from where their parents self seeded.
  • They are virtually trouble free, only requiring fertile soil and occasional pruning to keep them healthy and tidy.
  • They are usually pest free in my garden.
  • Family:                                                        Tropaeolaceae.
  • Garden bed type:                                           Drip line irrigated bed.
  • Recommended soil pH:                                  5.5 - 7.5.
  • Minimum Sun per Day:                                  6 hours.
  • Plant Size:                                                    Sprawling ground cover.
  • Good Companions:                                        Cucumbers, Zucchini, Brassicas, Apples.
  • Climate:                                                        Warm Temperate.
  • Geographic Hemisphere:                                 Southern. 
    Growing Conditions.
    • Nasturtiums need full sun.
    • They are frost tender, but in our climate usually survive well enough to give cover to new seedlings replacing them in spring.
    • They stand up well to hot dry conditions, but grow best if the soil is kept moist.
    Soil Preparation.
    • In Spring, tidy up the old plants and remove mulch and organic debris from under them.
    • Apply a 60mm top dressing of homemade compost, and cover with a thick layer of straw mulch. 
    Growing Instructions.
    • In spring, sow nasturtium seeds 100mm apart in the selected garden bed.
    • Once established, a patch of nasturtiums will maintain itself for many years by self seeding. 
    • Apply a foliar spray of aerated compost tea every 4 weeks when the other edible plants are sprayed.
    Organic Pest Control.

      • Nasturtiums needs protection against slugs and snails, so use self adhesive copper tape around the base of the bed to keep them out.
      • If its not practical to protect the garden bed in this way use iron based slug and snail pellets, in moderation, and only when they have become a problem.
    • Cabbage white butterfly caterpillars.
      • The best control of caterpillars is to spray the affected plants with Bacillus thuringiensis (Dipel in Australia)  This natural soil dwelling bacterium once ingested by the caterpillars produces toxins which paralyse the caterpillar's digestive system causing it to stop feeding.  It dies within a few days.
    • Greenhouse whitefly.  
      • A foliar spray of aerated compost tea improves plants resistance to whitefly damage.
      • Control any infestations by spray your crop thoroughly with organic horticultural oil (Eco-oil in Australia).
      • Spray again in a few days to ensure second generation whitefly do not survive.

    • Aphids (greenfly). 
      • Use the same method described above for whitefly.
    • General.
      • Repeated foliar sprays of aerated compost tea should deter most airborne pests and diseases.
      • Proper soil preparation and regular applications of home made compost should control soil borne pests.