Temperatures are climbing into the 90s, your spring-planted crops are reaching maturity, and you’re excited about garden fresh salads and new potatoes. Besides harvesting your bounty, there are millions of weeds to be pulled, poisoned, or decapitated. The last thing on your mind is planting more seeds.
In more benign climates, fall crops go in at the end of the summer, after the worst heat has passed. But our short season demands that we plant fall crops earlier, to give them time to mature before the snow flies. Now is the time.
Most members of the cabbage family—heading cabbage, kale, broccoli, kohlrabi, etc., produce their sweetest, most tender leaves, shoots, and stems when the days are short and the weather is cool. Kale, in particular, sweetens dramatically once the leaves have been kissed by frost. If we want to harvest these plants at their prime, we need to get them into the ground now.
Spinach is another crop that excels when planted as the days get shorter. Long hours of sunlight cause the stems to elongate into a flower stalk, a process called “bolting.” Bolted spinach becomes bitter and inedible. By planting after mid-summer, you can enjoy a long harvest of spinach leaves with no concern that the plants will bloom.
Lettuce may be grown from early spring to late fall. The key to continuous salads is to plant a few more seeds every week or so. At this time of year, the soil temperature may be too high for lettuce to germinate. If you don’t seem to have any luck, try sticking your seed packet into the refrigerator for a couple of weeks. This will fool your lettuce seeds into thinking it’s early spring, and they’ll sprout right away when they’re sown. (Another solution is to start the seeds indoors where it’s cooler.) During hot weather, lettuce benefits from a bit of shade during the middle of the day. Shade cloth stretched over the bed also offers hail protection for these tender leaves.
Bush green beans usually produce all their crop at once, and then either wither away or remain in the garden, bean-less. Once you have harvested the beans, it’s best to pull the plants and use the space for something more productive. To enjoy green beans all summer, either plant pole beans (which continue to produce new beans) or sow a short row of bush beans every two weeks. Most varieties take about two months to mature, so you can continue to plant until mid-July. One caveat: the shorter days and cool nights of late summer slow growth, and the days to harvest listed on the packet will be too short. Allow your crops plenty of time to mature, as beans are killed by the slightest frost.
Since transplants are unavailable in late June and early July, you either have to grow your own or start from seed. Aside from the added protection (from pests and weather) of starting seedlings indoors, there is really no advantage of dragging out the empty 6-packs and potting soil. In fact, plants seeded where they are to grow have stronger root systems, and don’t suffer from transplant shock.
Prepare your soil by adding some compost, perhaps a handful of all-purpose fertilizer, and turning it over with a spading fork or spade. Rake out any large clumps. Now carefully place one or two seeds where you want each plant to grow, covering them with a half inch of fine soil or vermiculite. Keeping your seedbed damp until germination will be the challenge. A hose-end mister on a faucet timer can help tremendously.
Once your seedlings appear and are growing well, thin each clump by pinching off the weaker plants, leaving the biggest and best to grow to maturity.
Yes, it’s hard to think about planting more vegetables when there’s already so much to do in the garden. But come fall, when you’re still picking crisp lettuce and sweet, juicy cabbages, you’ll be very glad you did.
Article and photos by Leslie Holzmann, Certified Colorado Gardener