Succession Planting Greens in Mid-Summer in PNW

I'm succession planting a lot these days (July) — mostly lettuce, pak choi, and arugula. I've worked out a few tricks for doing it here in the PNW. This isn't the only way, but it's what's working for me.

Lettuce

First off, I start lettuce indoors under grow lights. I don't trust my ability to direct sow, thin properly, and give each plant the right amount of space, so I'd rather control it from the start.

Step 1 — I spread roughly 25–30 seeds evenly across a 5" tray of moist seed-starting mix, then press them into the surface with my knuckles. Don't overdo the seeds — they're tiny, and too many gets you spindly seedlings that transplant poorly. I mist the soil with a sprayer, then set the tray under grow lights with a humidity dome. They should germinate in 3–5 days at 70°F. Once the seedlings are up, pull the dome and keep them watered — every other day or so.

Step 2 — In about 30 days the seedlings will be 1–2 inches tall and ready for a bigger pot. I transplant four into a 3.5" pot of potting soil, water well, and put them back under the lights. They'll establish and be ready to harden off in 1–2 weeks.

Step 3 — Now they're about 3 inches tall. I set them outside alongside a raised bed, in a bit of shade. I skip the greenhouse this time of year, it's a sauna in there. They'll be fine as long as you water daily. In three days to a week, they're ready to break apart and go into the bed.

Step 4 — On an overcast or not-so-hot day, transplant them in and water well. Sometimes I'll pour water into the hole first, set the start in, then water again on top. I water daily for a few days while they establish, and after that the drip lines take over. If a hot day hits, cover them with shade cloth — I keep hoops in the beds permanently, so it's easy to pull the cloth over and clip on. In mid-summer I'll often leave the shade cloth rolled up on top of the hoops, ready to go the moment I need it.

Arugula

I direct sow arugula, and then I do a funny thing where I move the crowded little seedlings around to even out the planting. It's a fast crop: full plants ready to harvest in about 30 days.

Step 1 — Smooth the soil mostly flat. Scatter the seeds all over, then lightly brush the soil with your hands to half-cover them. Water in. Then keep watering every day — sometimes twice a day — to get them going. If I don't see seedlings after a week, I'll resow and water in again.

Step 2 — Seeds are hard to distribute evenly, and there's no telling which ones will come up. So when I see clusters — even seedlings with just two little leaves — I'll scoop up a handful and move them to the bare spots. Water in well.

Pak Choi

I direct sow pak choi too, but the birds love to nibble the little leaves, so I put floating row cover over a newly seeded bed to keep them off. Otherwise, the leaves end up looking like a mini-chainsaw had its way with them.

Step 1 — Clear out the previous planting. If it's the third round, I may add more fertilizer. I scrape rows about ½" deep and 3" apart with my fingers, drop seeds every inch or so, then rake my hand back over to lightly cover them. On goes the row cover, held down with rocks in the corners. Water in well, and daily until you see seedlings.

Step 2 — If I get around to it, I'll thin the seedlings that are too close together — 2–3 inches apart is great. But I leave the row cover on until the plants are about 2 inches tall. The birds seem to lose interest after that.

Resources I've found worth having for starting greens:

• Garden hoops - I use these double wide ones that are more sturdy.
• Floating row cover - Agfabric is good this is the one I use
• Shade cloth - 30% is good for the PNW
• Garden clips - inexpensive and necessary.