Why breakfast matters - Feeding plants in the greenhouse

potting soil being placed in compostable pots

Truth be told, I can easily ignore a bit of soil spilled on the benches or an occasional unsterilized pot for seedlings. I don't always wear gloves, or fastidiously wash labels. I like the results in my greenhouse. My Sweet Peas bloom early, my tomatoes grow fat on the vine. A little mess, a few germs - my plants and I are no worse for the wear.

But I have become a bit fastidious about fertilizer. I used to reason that young plants needed to get tough from the get-go, that feeding would make Slow release fertilizer placed on soilthem unprepared for life in the real garden. But as much as I wanted to ignore anything that required more attention to detail, I saw that if I fed my plants wisely - seedlings, cuttings, and even over-wintered half-hardy treasures – they were a bigger, more resilient, more ready for life in the real Greenhouse Garden.

My newfound fastidiousness started with cuttings. Early one July morning, I took a few stems of Hydrangea and Clematis, and after securing them well in a mix of compost and lots of perlite, I soaked the flat of cuttings in water to which I had added 2 capfuls of liquid fertilizer.  For a couple of weeks, because I had the jug on my shelf, I continued to soak them in a weak version of the same solution.

Three weeks later I noticed two Hydrangea I had neglected to include earlier, so I raced to mix up more compost and perlite, and quickly propagated a new flat of baby Hydrangea cuttings.  But in my hurry, alas, I skipped soaking the flat in water. A good sprinkle of water overhead had to suffice.

About a month later, I realized that the first batch not only rooted more easily but the plants were more robust. I cringed, wondering if that added labour of soaking them in the nutrient-rich water may have made a difference.

I didn’t dwell on these differences until I was pricking out seedlings the following spring. After tenderly separating apart the seedlings into cell packs, four little leaves splayed out wide and eager, I again added a capful to my soaking water and had them bathe in the enriched water every other day for two weeks. The results spoke louder. My seedlings seemed to have less transplant shock than usual; they seemed heartier and more upright.Planting in compostable pots

Still suspicious, I did some research. What studies show, quite consistently, is that seedlings and cuttings that live in containers, prosper with a bit of added nutrients. It is the container life that creates the crucial need. Because nutrients leach out quickly with frequent watering, supplying the nutrients through fertilizers can make a significant difference to a plant’s health.

To offset my sloth and haste, I now keep red and green cans. I now serve breakfast regularly.  I add one capful of my Quick Start to my red can, as it boosts my young plants, needing to build strong roots to get them on their way.   To my green can, I add 1 capful of all-purpose food (mine is 20-20-20).  I switch from the red can to the green can when the seedlings or cuttings are well established and growing vigorously. Using half of the recommended dosage works well because I use only these cans, approximately 3 times per week, instead of once a week with regular watering in between.  My lazy person’s approach is to use a weaker strength more often, thereby never having to think which can to use, when.