Salad Days 2013: Propagated Peas

Peas ready for their propagator experiment. The left tray has the beets I told you about on Monday

Last year I grew pea shoots for the first time. Lots of them. I found a small tray of thickly sown peas (either sourced from shop bought or the remains of a seed packet) were sufficient to form the 'base layer' with added sprouted seeds and microgreens to make a hearty salad for two.

I see from last year's notes it can take up to 6 weeks for the pea shoots to crop during the darkest months. Later sown crops steadily grow just that little bit faster week by week, until growing them takes around four weeks in March. I was therefore keen to explore if growth time could be speeded up in some way.

Experimental peas doing their stuff

We spotted during last year's 52 Week Salad Challenge that a sharper cold spell could check indoor growth almost completely for a while. Temperatures can still fall quite sharply at night behind the curtains, even when the windows are double glazed.

I had a bit of a 'light bulb' moment over the Christmas holidays and decided to press my new propagator into service to see if its protection would affect pea shoot growth in any way. I could use identical trays, with the same amount of growing media and peas added - 50 per tray and pre-soaked so they germinate more quickly. The trays could then sit side by side on my south facing bedroom windowsill with and without their lids. I left them sitting there quietly and had a look each morning with notebook in hand to see what was what.

Here are the results:

The lidded peas appeared a day earlier than the unlidded ones, on day 4 (7th January). Both trays of peas reached their maximum number of germinated seeds on the same day, day 10. Whilst the germination rate of the tray with a lid is higher, I don't think it's sufficiently high enough to be significant as both sets of peas had a relatively poor rate of germination (38% for the lidded peas and 30% for the unlidded). This is probably because the packet of seeds I was using up was right on its sow by date.

However, the better performance of the lidded peas has continued post germination. The lid was left on until some of the peas reached lid height on day 13 (15th January). I measured the height of the peas in each tray and found an average of 88 mm for the unlidded grown seeds and 105 mm for the lidded ones. This marked difference in growth has continued. On Tuesday this week (day 20) the peas' average heights were 104mm (unlidded) and 143mm (lidded).

Peas waving happily at the snow

If this difference in growth continues, then it looks like I'll be harvesting the lidded peas 2-3 days earlier. This might not sound very much, but it means an extra crop of pea shoots could be squeezed in over an autumn/winter/early spring growing period. I'll update this post with actual harvest dates later. As you can see, (unlike the beets next door) the peas haven't suffered from the dreaded damping off disease this week.

Therefore using a lidded propagator could be a useful way of bringing on windowsill grown pea shoots a little more quickly for no extra outlay, assuming you already have one. I'm saying could because I need to see if these results are repeatable rather than a one-off occurrence. It'll also be interesting to see if the observed difference in growth rates changes with increasing light.

I'm beginning to wonder if peas are a suitable small crop for this time of the year because their very nature is to be leggy, unlike their beet cousins grown alongside. These were looking a tad stretched before they succumbed to damping off. I'm also pondering whether the height of my bedroom windowsill is key to a successful early crop at this time of year. A comparison with a tray grown on my kitchen windowsill downstairs could be interesting. So, the experiments will continue :)

In a future post I'll be looking at another useful technique for producing earlier crops without needing a greenhouse or polytunnel to do so. It does however, require much more space than my windowsill...

How's your salad coming along? Either let me know in the comments, or leave a link to your salad filled blog post in Mr Linky below: