Spring in the Greenhouse

zuchinni and living mulch mustard and marigoldEarly zuchinni, african marigold + mustard

It’s mid spring in the greenhouse and no bare soil remains. Once the heat starts, so too the pressure on the soil so I keep things healthy with a mixed living mulch. Apart from lupin, which I sow after the chooks have been through, the rest are that wonderful guild of super useful plants – self seeders.

The greenhouse began like all of my other gardens, full of buttercup, dock, nightshade + grass. Deep mulching and weeding while small eventually got on top of the plants I didn’t want. Tossing seed of the plants I did want in their place filled it back up in the way I wanted. Letting the chosen ones goes to seed means I can remove myself from this job ever after. The greenhouse groundcovers are set in play.

Borage for Bees

  • One of our best friends in the organic garden is borage and I’m happy that she survives all but the hottest months in my greenhouse. I need her to bring in the bees and nourish the soil.
  • African Marigold and Shoofly help deter pests above and below ground and feed the bees as well.

  • Nasturtiums are another key player – winding through the lemongrass, under the grape, around all the edges and up the walls as far as I’ll let her, providing a catch crop for aphids and piles of mulch material.
  • Nourishing chickweed and cleavers thrive in spring but die off when it heats up, recycling all their goodness back.


  • Mustard is a bio fumigant for the soil as well as flowers for bees and fodder for mulch.
  • Lupin provides bursts of nitrogen as long as I don’t let her flower and a lovely deep tap root.

The simple act of tossing about seed brings so many benefits. These humble plants keep the soil active, beat out weeds, moderate soil temperature and help hold moisture. When they get too bossy I simply break them off and pile them on the soil as mulch. Chop and drop mulching is a quick easy job that beats weeding any day.

greenhouse cukes

By late September when the first cucumbers, tomatoes and zuchinni go in, the ground is cloaked in green. As I need to, I create spaces to plant into, chopping back the greenery and using it as mulch. As the crops grow and fill the space I chop back more and more groundcover until come January the jungle is mostly tomatoes, peppers, eggplants, basil and cucumbers instead.

greenhouse tomatoes planted amongst saladings ediblebackyard nz

There’s a line to walk here between healthy airflow and being wild. The season dictates how this plays out – and every year is different. When it’s wet and hot, I chop back the jungle as risk of fungi peaks in this plastic coated room. When its hot and dry, the jungle improves cropping no end.

Topping up your mulch regularly with fresh material is a simple but hearty way to look after your greenhouse soil. How efficient (and we could say resilient) to use the stuff that grew there to do this job. Full circle, homegrown and perhaps best of all, plastic bag free gardening.

This morning while I was watering, I rescued the dwarf beans from a salad/ nasturtium takeover bid. I picked the salads for tea and the rest of the ‘weeds’ became mulch.

pre weeding

Beans being outdone by salads and nasturtiums

Chop and drop enough just to create good light and air.

beans rescued

Beans are rescued!


  1. Kate Mcadam says

    Thanks for the info Kath. Your green house looks awesome. I’m hoping to build something like this. What a paradise you have created

    • Nice to hear from you Kate! I highly recommend a greenhouse 🙂 worth the effort for sure not only for all the food it brings but a warm, cosy escape… girl shed!!