The Plant Lady: It’s time to plant cool-weather crops. Here are my best garden tips

With temperatures in the 90s, the last thing on most people’s minds are cool-season vegetables. But while your summer veggies may just now be hitting their stride and pumping out produce, but now is the time to start planning and planting winter vegetables.

The key to growing healthy plants is healthy soil. Before planting or sowing seeds, make sure your soil has enough nutrients and beneficial microorganisms to sustain your plants the entire growing season. If you “feed” your soil, then fertilizers are not necessary. A healthy soil can be achieved by adding compost of your own making or store bought compost/soil amendments. Some composts have added nutrients and may be labeled as garden soil, soil booster, planting mix, garden mix, planter mix or vegetable soil. Most of these contain composted plant material, but have added manures and biologicals such as kelp, earthworm castings and mushroom compost. If using one of these blends, make sure to mix well into your existing soil. If growing in raised beds, a good quality potting soil is recommended, but the aforementioned compost/amendments can be added after each planting season to replenish the soil.

Despite temperatures being warm when planting and sowing, winter veggies need full sun to achieve their optimal results. Keep seeds and plants moist but when winter rains (hopefully) arrive, leave the watering to mother nature.

Broccoli and Cauliflower

Broccoli and cauliflower can be planted in two rounds. In August, plant the first round for a fall harvest and then a second round in February for a spring harvest. When broccoli or cauliflower are planted too late, the plants will form very small flower heads and quickly set seed. If you happen to do this, all is not lost, as all parts of broccoli are edible (as well as the leaves of cauliflower). But if large clusters of flower heads is what you want, then timing is key.

Brussels sprouts

Plant Brussels sprouts in August or September for a late fall/early winter crop. To encourage the sprouts to form, you can cut the top off of the plant once it has reached a healthy height (12 to 18 inches). This will divert hormones and trigger side growth (sprouts). Jade Cross is considered the best cultivar for warm season climates.

Some crops do best or are so easy to grow from seed that I recommend it over starter plants. Carrots, beets, radishes, turnips, leafy lettuce, chard, kale, spinach and peas fall into this category. For a continuous harvest, plant these crops in 1 to 2 week intervals starting in August.

▪ Carrots do not transplant well, as any damage to their tap root will result in poor success.

▪ Pea seeds should be soaked in lukewarm water overnight before planting.

▪ Note that radish seed pods are just as tasty as radishes and very plentiful, so consider growing some plants for their seed pods. The pollinators will love the flowers as well.

▪ When direct sowing it is key to keep the soil moist but not oversaturated.

Bolting

One of the most disappointing aspects of winter veggies is their ability to bolt. Bolting is when a plant goes to flower/seed before generating any viable produce. Broccoli, onions, lettuce and Brussels sprouts are the most common to bolt. The key to avoidance is planting at the correct time — but even then bolting can occur based on weather fluctuations.

Onions are notorious for bolting. When planting, be aware that there are long, neutral and short day cultivars. In Zone 9, it is best to plant short day varieties since seeds are sown in August and plants set out October- January. When onions bolt they will go to flower/seed without forming a bulb. If this occurs, they can still be harvested for their leaves.

Pests

Winter crops are magnets for two main pests, cabbage aphids and the cabbage white larvae. Cabbage aphids are gray, with a very thick waxy coating which makes them very difficult to control. Soap sprays and neem oil work, but the key is repeated sprays every few days. As an alternative, I recommend a vigorous hose blast. If you see small white butterflies flying around your plants, be aware they are laying eggs on your plants. Those eggs will result in larvae that can devour young plants. The telltale signs are large holes or sections of leaves chewed. Additionally, you may see their black excrement. You can hand pick off the green larvae from underneath the leaves or use BT. BT is a natural bacteria (Bacillus thuringiensis) that they ingest but cannot digest. BT is found at almost all nurseries in spray or dust form.

If starting from seeds, birds can pick your seedlings. My go-to bird protection are overturned plastic nursery flats — ideally use the ones with bigger openings. They are much easier to work with than bird netting. Also, let’s not forget that snails and slugs love to chew emerging seedlings. Iron phosphate (Sluggo) is the best organic control for these pests.

Need garden planting help?

A great resource for planting dates is the Sacramento Master Gardener’s planting guide, found at http://sacmg.ucanr.edu/files/117117.pdf