Water, temperature and plant spacing can mean success or failure for your veggie starts

MANY OF US HAVE JUST PLANTED our vegetable starts and have high hopes for them.

Each small plant represents the physical initiation of a lengthy process that begins in our imaginations. We may have bought or grown the small plants, but it’s when we plant them in the soil that our real connection with these living entities begins. Their success depends entirely on us - our efforts and ability to recognize and provide what they need to thrive. In our hands the plant is small, but in our mind, it’s already a harvestable size and waiting for us to use its leaves, flowers or fruit to feed ourselves and our community.

How many of us go out each day to the garden and watch the plants, visually measuring them to see how much they’ve grown since the day before? Day-by-day growth can be imperceptible, but you can discern growth every two days.

Adding compost and organic fertilizer to the soil, whether in a raised box or in-ground bed, should be enough to get plants growing well. Soil temperatures matter, too.

Plants grow slowly or even can exhibit nutritional deficiencies like chlorosis (yellow leaves with green veins) when soil temperatures are below 60 degrees. Raised beds heat up more quickly than in-ground soil so plantings in them often initially grow more quickly.

I measured the soil temperature in raised beds and in-ground beds in early April and found that the soil in a raised bed about one foot tall was 65 degrees. A two-foot tall raised bed was 68 degrees. In-ground soil was 62 degrees. Plants there were growing much more slowly. Warmer temperatures found in raised beds benefit plants now, but in hot summer areas of our region, these beds will heat up and dry out quickly, so they will need more frequent irrigation.

Also, many fertilizers like nitrogen are water soluble, so the more the beds are watered, the more nutrients like nitrogen leach out. Raised beds likely will need additional fertilization as the summer progresses.

As you plant seedlings or direct-seed vegetables, even if you have drip irrigation, water them in well with a hose for best results. When temperatures are in the 70s or 80s, hand water seedlings daily for several days.

Dramm-brand water breaker nozzles or something similar are the best choice for watering. These nozzles are round with between 400 and 1,000 holes. The more holes, the softer the spray will be. The heads come in both steel and plastic.

If you live in an area that regularly freezes in winter, you probably will want to purchase the steel type or bring the plastic (and cheaper) nozzles inside in winter so water doesn’t freeze in the heads and burst them. These watering heads can be screwed onto a watering wand.

As direct seeded seedlings emerge, you may need to thin them. Wait until they are a couple of inches tall to gauge survival rates. Summer squash, pumpkins, carrots, beets, radish, beans, onions, Japanese or Chinese greens, spinach and mini greens are typically direct seeded.

Thinning can be tedious, but it is necessary so plants can mature without competition. A pair of scissors with thin, pointed blades is a handy tool for this purpose. Pulling out plants can disturb the roots of neighboring plants.

You may want to do an initial thinning, so seedlings are a couple of inches apart, then a secondary thinning to the mature spacing as plants grow, to ensure you have enough that survive.

Sometimes purchased seedlings have more than one plant in a pot. Many vegetables should be thinned to one at the time of planting or a few days later when plants have established. Plants like broccoli, kale, cauliflower, cabbage, pac choi and bok choi don’t form large heads and may flop if crowded.

Carrots, beets and other root vegetables will have smaller roots. Lettuce and spinach are more forgiving when crowded. Each summer squash plant or pumpkin is large and needs room.

Keep a close eye on growing seedlings. Going out in your garden daily to check on plants helps circumvent problems as any issues can be addressed when damage is small. Make sure to patrol and look for slug or snail damage and bait with nontoxic baits as necessary or pick off snails early in the morning when they are active.

Kate Frey’s column appears every other week in Sonoma Home. Contact Kate at: katebfrey@gmail.com, freygardens.com, Twitter @katebfrey, instagram @americangardenschool