UNITED STATES—Right smack in the middle of the warm part of summer, it is already time to be getting ready for autumn gardening. This involves more than just ordering our autumn planted spring bulbs while the selection is still optimal. Most of us purchase bulbs from what is available in nurseries when they are in season anyway. Seed that gets sown in the next few weeks is a more immediate concern.

The majority of cool season vegetables will get planted later, when the seasons actually start to change to become . . . well, cool. Seed for beets and carrots gets sown directly in about a month, followed by pea seed even a bit later. At about that same time, many of us will plant small seedlings of other cool season vegetables, like broccoli, cauliflower, cabbage, lettuce, spinach and kale.

For many of us though, it is not that simple. If we want varieties of these cool season vegetables that are not likely to be available as seedlings in nurseries later, we must grow our own from seed. Whether they get sown directly into the garden, or into flats to be grown as seedlings to be planted later, broccoli seed should be sown about now. By the time it gets to growing, it will be autumn.

Seed purchased online or from mail order catalog should be ordered by now. It is not too late for broccoli if the seed arrives and gets sown soon. Cauliflower and cabbage seed gets sown within a month or so, as late August becomes early September. Lettuce and spinach seed should wait half way through September, like beet and carrot seed. Kale seed can wait until after September.

Seed for secondary phases of most of these cool season vegetables can be sown early next year.

In the meantime, warm season vegetables must continue to be harvested very regularly. If they stay in the garden long enough to get tough and bland, they also interfere with continued production. Foliar herbs can be harvested for drying just about any time they are fresh and not blooming. Regular harvesting inhibits bloom, and therefore promotes more of the desirable foliar herbal growth.

Highlight: Chilean jasmine

This is not just another mandevilla. Well, maybe it is. Mandevilla laxa is special though. It is known as Chilean jasmine because, unlike other mandevillas, it is so delightfully fragrant, particularly on warm summer evenings. Some say the fragrance is similar to that of gardenia, but not as strong. Others say it has a bit of vanilla mixed in. Sporadic bloom continues through most of summer.

The two inch long pure white flowers flare out to be a bit wider than long, and are a bit more relaxed than the neatly tailored flowers of other mandevillas. They bloom sequentially in small groups, with new flowers replacing the old for quite a while. The glossy rich green leaves can get almost twice as long at the flowers. Foliage last better on the coast, but is mostly deciduous elsewhere.

Chilean jasmine grows fast in spring, especially if pruned well after winter, but is surprisingly tame. It can grow past downstairs eaves, but should not reach upstairs eaves. It is satisfied with a light duty trellis. If carefully pruned out and removed each winter, it is one of the few vines that is complaisant enough for lattice. Light frost can kill stems to the ground, but they usually recover in spring.

Horticulturist Tony Tomeo can be contacted at tonytomeo.com.