As the sunlight increases, so does the gardener’s workload. There are so many things to do this time of year in preparation for outdoor planting.

If you’re planning on growing members of the brassica family, which includes cabbage, cauliflower, broccoli, and Brussels sprouts, it is critical to transplant them outdoors at the proper growing stage. For some reason, when the seedlings have between five and eight leaves, they are particularly sensitive to the stresses of fluctuations in temperature, drought, and disturbed roots – all common occurrences at transplanting time.

The strange thing is, damage from stress may not show up for weeks. Then, the cauliflower transplants that appeared to be growing normally may develop only small heads, called button heads, or bracteated heads, where leaves grow from between the curds. Sometimes, the tip of the plant will simply die. For cabbage, the result of stress may be plants that bolt (go to seed) instead of growing a normal head.

Avoid these and other stress-related problems by planting the seedlings outdoors when they’re still very young or by waiting until the plants have at least nine leaves. Another option is to start at least three plantings, a week to ten days apart. That way, whenever you choose to transplant them, at least some of the plants will be at the proper stage. Of course, you can direct sow but be sure to plant early – two to six weeks before the last expected frost – as the brassica family does not like warm weather.

Now is also the time to be planting tuberous begonias and other tender tubers, corms, bulbs, and rhizomes. Most of these “bulbs” (I’ll refer to them all as bulbs in this article) like a warm soil – 70-80 degrees – although they will grow as long as the soil is above 60 degrees.

These tender bulbs, with a few exceptions, should be planted indoors six to eight weeks before the last frost date. Using a soiless mixture that is damp but not wet, follow the directions that come with your bulbs. For example, begonia tubers are planted hollow side up and covered with about a half an inch of soil. If you’re not sure which side is up, carefully lift the tuber in a few days to see which side is sprouting roots, and which is sprouting shoots and replant accordingly.

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When planting hanging begonias, be sure to remove the tip of the first shoot while it is still small. This promotes branching and, as a result, a fuller plant.

Other “bulbs” you might want to investigate are dahlias and glads. Although dahlias are often planted directly in the ground after soil has warmed and all danger of frost is past, the tubers can be started in pots about a month ahead of the last frost. Only use tubers in good condition – discard if rotted or dried out. Make sure each piece planted has a growing bud attached.

Gladiolus can also be started indoors a month before the last frost. They should be planted in well-draining soiless mix with extra vermiculite or perlite added. The pots should be at least five inches deep.

As all your pots and flats and other containers take over every square inch of space in your house, I wish you an understanding and supportive family and a nice set of TV tables so you have a place to put your dinner (if you haven’t put seedlings there, too).


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