How to succeed with transplanting crops

Young senposai transplant.
Photo Pam Dawling

I wrote very recently about Direct Sown Vegetable Crops

There I referred to my Nov 2021 post, Preparing for Spring Transplants  (handle replacements, seed compost, aphids, soil blocks, Winstrip trays).

I have written previously about the Advantages and Disadvantages of Direct sowing and Transplanting and also about  using Bare Root Transplants.

Here I am going to give many tips for success with transplants.

Succeeding with transplanted crops

Tomato transplants in pots, ready to plant out in mild weather. These are for our hoophouse. Outdoor tomatoes are started here in March.
Photo Wren Vile
  1. Grow good transplants: sturdy, not spindly; good size cells or good depth flats; grow enough plus 20% (less for kale, more for melons)
  2. Harden off for two weeks before transplanting: cold frame. Cooler temperatures, more breeze, brighter light.
Flats of transplants in our cold frame ready for transplanting.
Pam Dawling

3. Prepare the bed or row: detach all weeds (hoe). Loosen the soil (till or broadfork as needed).

4. Stale seed bed technique: water, hoe off the new weeds. Hoe the day before transplanting (easier to hoe soil without crop plants to work around). Or tarp to smother weeds. Or use an organic mulch to smother weeds, once the soil is warm enough for that crop.

5. Mark the row spacing with a row marker rake, or lines in the soil with the corner of a hoe, or stakes and string. Don’t plant too close to the bed edge, or navigating the path becomes tricky (and wet in the morning dew). To plant two rows of broccoli or chard in a 4 ft (1.2m) bed, I’d set the two rows 16-18” (41-46 cm) apart, with 16-15” (41-38 cm) between the row and the bed edge.

Johnny’s Bed Prep rake with row marker pegs.
Photo Johnnys Selected Seeds

6. Water your transplants well on the day before transplanting.

7. Check you still have enough plants for the desired spacing. This is your last chance to make the space between one plant and another bigger (if you have fewer plants now), or smaller (to fit in some extras, perhaps sacrificing the size of each head).

8. Either mark the spacing now, with a rolling dibble or using a measuring stick, or mark them as you go along transplanting. I prefer to offset the rows, so they are in a zigzag from each other, rather than have them square set, where the plants are directly opposite those in the next row. The offset method gives each plant the most even space all round before it encounters roots or leaves of its neighbor.

A bed of young transplanted lettuce, with plants in each row offset from neighboring rows. the plants form diagonal rows, easy for hoeing.
Credit Wren Vile

9. Plan to transplant late in the day, unless it is cool and overcast, or drizzling (“ideal transplanting weather”. The plants then have the cooler night to recover from the surprise of transplanting before facing hot or bright sunshine. It really makes a difference! You can get everything ready earlier in the day: shade cloth or rowcover and weights to hold it down, wire hoops if needed, watering equipment (cans or hose), labels, tools.

10. Water thoroughly again one hour before transplanting. This ensures the plant cells are holding as much water as they can before their roots or root hairs get a bit damaged during transplanting.

Transplanting spinach from a Speedling flat. Butter knives are the tool of choice for easing the little wedges out of the tapered cells.
Photo Denny Ray McElya

11. Pop a transplant out of its cell, holding it by a leaf if possible, not the stem (there are spare leaves, but no spare stems, and you want to preserve all the roots too). Develop a good technique in order to preserve the life of plastic cell packs. Perhaps tilt the cell pack diagonally and squeeze the bottom of a cell, pushing the plug upwards. Perhaps use a butter knife to slide down the side of a cell and flip the transplant upwards while holding the plant with your other hand. Some plug flats have holes in the bottoms of the cells, where you can push up with a finger or a dowel. All the soil/compost in the cell should come out with the plant. You are definitely not “digging” the plants out of the cells.

Transplanting bare-root spinach.
Drawing by Jessie Doyle

12. Or scoop a plant out of an open flat with a good handful of compost, keeping your hand under the root-ball. This gets easier once the first plant has been extricated.

13. Make a big-enough hole in the soil where you want to plant, without actually digging out any soil. It’s a waste of time to make a pile of soil. Try instead to insert the trowel to the correct depth and wiggle it back and forth to open up a slot. I like the Wilcox stainless steel trowels rather than the “traditional” wide scoop-shaped trowels for transplanting. We have Wilcox 102 and 104 models, and the smaller 50S.

Wilcox 12″ (30cm) 102 stainless steel trowel.

14. Slide the plant into the hole, keeping a hold with one hand, so you can set the plant at the correct depth. Use the trowel in the other hand to push or pull soil back into the hole until it is filled.

15. Press the soil down around the stem quite firmly. You don’t want compressed soil that won’t drain well, nor do you want loose soil with lots of air pockets, as these prevent roots from drawing water from the soil. Good root contact with soil is important. I was taught to take the end of a leaf after transplanting and tug gently. If the leaf tears, you have planted firmly enough. If the plant pulls out of the ground, try again.

16. For a long, satisfying gardening life, develop a technique where you don’t set the trowel down. Just keep it in one hand and do the other tasks with your other hand. This will be more efficient. Gardeners with only one working hand will have to ignore this piece of advice, of course.

17. If you have not pre-marked your planting spots, measure to the next spot. You only need to measure one row in the bed, as it works better to eyeball the other rows.

18. Continue until you have been transplanting for 20 minutes, or 30 minutes in cooler overcast conditions, then pause and water in what you have planted.

19. Some people prefer to have a watering can beside them and water each plant immediately after planting. If conditions are very hot, this is definitely best. Otherwise, I make faster progress in 20-30 minute sections. Another alternative is to use a hose with a valve on the end. The goal is 6-12 seconds of water per plant, depending how free draining your soil is and how fast the water is flowing.

Spring cabbage planted in hay mulch, a few weeks after transplanting.
Photo Kathryn Simmons

20. Remember, with transplanting, you have the opportunity to select the sturdiest plants and leave the wimps in their cell or a corner of an open flat, for replacing casualties in a week. Really poor specimens can be thrown over your shoulder!

21. When you finish planting, install any hoops, shadecloth or rowcover and weights.

22. Water the plants well the following day (day 2), and again on days 3,5,7, and 10, if it doesn’t rain well.

23. After that give an inch of water a week, if nature doesn’t. To determine your watering rate, set a vertical-sided empty tuna can or other shallow container in the row while you water (or while it rains).

One of our impact sprinkler tripods, in a broccoli patch.
Photo Pam Dawling

Also see Spring broccoli planting and here.

We aim to plant out our broccoli in the first two weeks ofApril. We may have delays due to wet soil. When we plant late (and big), we sometimes struggle to keep them thriving if the weather is hot. The we have to water a lot, even though the soil was still saturated from the heavy rains.

In those posts you can read about how we mulch our spring broccoli and cabbage planted in temporary raised beds, 4ft (1.2m) wide with one foot (30 cm) paths. We unroll big round bales of spoiled hay over the beds and the paths too. We make two rows of “nests” in each bed, using a measuring stick to get the right spacing. We use our hands to tease the hay apart down to soil level. Then we transplant, water in and close the hay over the soil around the stem of the plant. We cover with rowcover to protect from cold nights, bugs and stiff breezes. We use sticks to hold the rowcover down, rolling the edges under rather than over, which helps them stay in place and not tangle with hoses or feet.

Not much to see – spring broccoli under rowcover.
Photo Kathryn Simmons

Not much to see – spring broccoli under rowcover.
Photo Kathryn Simmons


Sowing hoophouse winter crops

New spinach seedlings in our hoophouse.
Photo Pam Dawling

We are on our way with our late fall, winter and early spring crops in the hoophouse. On September 6 and 7 we sowed five crops in our first bed – spinach, tatsoi, Bulls Blood beet greens, radishes and scallions. On September 15 we sowed lettuces, chard, pak choy, Chinese cabbage, Tokyo Bekana and Yukina Savoy, in an outdoor bed to be transplanted into the hoophouse in a few weeks, after we’ve prepared another bed.

Broadfork from Way Cool Tools.
Photo Way Cool Tools

To prepare hoophouse beds for winter crops, we first remove the summer crops to the compost pile, then spread a generous layer of compost over the surface. We use about five wheelbarrowsful for one bed 4’ x 90’. Next we move the three lengths of drip tape off to one side or the other, and broadfork the whole area. We have an all-steel broadfork from Way Cool Tools that we really like. To use a broadfork, work backwards either going the length of the bed or the width. Stab the tines into the soil and step on the crossbar, holding the long handles. Step from foot to foot until the bar touches the soil, with the tines all the way in, then step off backwards, pulling the handles towards you. This loosens a big area of soil, which hopefully crumbles into chunks. Lift the broadfork and set it back in the soil about 6” back from the first bite. Step on the bar and repeat. We’ve found it’s important to only broadfork the amount of space you have time to rake immediately, otherwise the warm hoophouse conditions dry out the soil and make it harder to cultivate into a fine tilth, which is the next task. Sometimes we use a rake, breaking the clumps up with the back of the rake, then raking the soil to break up the smaller lumps, and reshape the bed.

7″ stirrup hoe.
Photo Johnnys Selected Seeds

Sometimes we use a wide stirrup hoe very energetically. This isn’t the job scuffle hoes were designed for (that’s very shallow hoeing, and hence why we call them scuffle hoes), but the sharp hoe blade does a good job of breaking up clumpy soil. We’ve also found it important to lay the drip tapes back in place in between each day’s work, so that the soil gets irrigated when we run the system and stays damp. We don’t want dead, baked soil.

Once the bed is prepared, we measure out the areas for different crops and mark them with flags. Next we use our row-marker rake (bed prep rake) from Johnny’s Selected Seeds.

Johnny’s Bed Prep rake with row marker pegs.
Photo Johnnys Selected Seeds

We plant crops closer in the hoophouse than outdoors, and closer to the edges of the beds. We don’t have many weeds in the hoophouse, and the paths are marked off with twine, to keep us from stepping on the beds, compacting the soil. We find that the soil does slump and compact some of its own accord, even if we don’t step on the edges (and of course, some feet do find themselves on the bed edges sometimes), hence the once-a-year broadforking. We found out how valuable the soil loosening is, because one year before we started broadforking, we decided to loosen the edges with a digging fork to make up for several years of accidental steps. The edge rows of spinach grew much bigger than the inner rows, and we realized that the whole bed needed loosening.

After the rowmarking, we deepen the furrows if needed (often it’s not needed), using a pointed hoe, then sow the seeds. We pre-sprout our spinach for a week in a jar in the fridge. Just soak the seed overnight, drain it in the morning, fit a mesh lid on the jar, and lay it on its side in the fridge. Once a day, give the jar a quarter turn to tumble the seeds and even out the moisture. This year the seeds were a bit wet when I came to sow them, and clumped together. I poured them out on a cloth to dry a bit before I sowed. This year we are growing two varieties (Avon and Reflect) side by side, still seeking a replacement for our much loved Tyee, which was pulled from the market, because it was prone to a disease prevalent in the West.

Easter Egg radish seedlings in our hoophouse.
Photo Pam Dawling

The spinach, tatsoi and radishes came up very quickly, with the beets a day or two behind. The scallions came up in a week, which is quicker than at other times of year.

One week after the sowings, I thinned the spinach and radishes to 1” apart in the row. We are growing Easter Egg, Cherry Belle and White Icicle radishes. The Cherry Belle will be ready first, Easter Egg next (they mature relatively gradually, giving us a nice harvest period). Icicle are unusual long white radishes which are slower to mature, and slow to get woody.

Buckley One-cut (Eazileaf) lettuce.
Photo High Mowing Seeds

Meanwhile, outdoors on September 15 we sowed the first half of the crops that we transplant bare-rooted into the hoophouse. Our planned schedule called for 10 varieties of lettuce, but I ended up sowing 12, partly because we are trying three new Vitalis one-cut lettuce varieties from High Mowing Seeds: Ezrilla, Hampton and Buckley.  These are bred to provide lots of similar-sized leaves from cutting. They can be cut and mixed for baby salad mix or cut as whole heads for easy-to-prepare salads, or harvested by the leaf (or layers of leaves) once the plant has grown to full size. This is how we use them. They were previously called Eazileaf varieties, and are now called One-cut lettuces. They are only available as pelleted seed, so I regard them as too pricey to grow for baby salad mix, and best used for multiple harvests.

Johnny’s Green Sweet Crisp Salanova lettuce.
Photo Johnnys Seeds
Osborne’s Multigreen 3 lettuce.
Photo Osborne Seeds

You can click here to read the New Head Lettuces article Andrew Mefferd wrote about this new type of lettuce in Growing for Market magazine. We have previously grown Johnny’s Salanova and Osborne’s Multileaf varieties and I wrote about them here and here. This year we are trying the High Mowing ones. We did a small trial of them outdoors in spring, knowing that in our climate (very different from High Mowing’s in Vermont) they might well bolt. They grew into handsome plants, but clearly they are more suited to fall than spring in our quickly-heating-up climate.

Other lettuces we sow for our winter hoophouse crops include Oscarde, Panisse, Tango which have a similar shape of lots of same-sized leaves, and Green Forest (romaine), Hyper Red Rumpled Wave, Merlot, Revolution, Salad Bowl and Red Salad Bowl. I would have sown Red Tinged Winter but we seem to be out of seed.

Red Salad Bowl lettuce.
Photo Bridget Aleshire