This is a good time to take rose cuttings. If you can keep an eye on them, start them in a pot of sandy soil, with or without a plastic bag over them.
June is so wretchedly wet, as a rule, that cuttings frequently root without any glass or plastic protection to keep them humid and turgid.
It is possible to root the cuttings stuck right in the ground where one wants them to grow permanently, but of course this is chancy. Sometimes it works well, then again not. Some people cover the cuttings with glass jars.
Usually they root best in filtered light, as in pots beneath a high-branched tree. However you handle them, the trick is to keep them from drying out on the one hand and rotting on the other.
The best wood for cuttings is just below flowers that are just fading. Cuttings four to six inches long are taken -- the flowers, if any, are cut off first -- and leaves on the bottom half of the cutting are cut off at the stem. I usually leave only two pairs of leaflets at the top, since I think it makes less demand on the twig for water in the several weeks before roots sprout.
Others, however, leave the top leaves entire, not trimming away any. It does not hurt to make a lot more cuttings than seems reasonable, since failure is common with these rough and ready methods.
If these cuttings fail to root, try again with eight-inch cuttings in the fall. They can be covered with glass jars. The leaves fall off and the sticks look fairly sad all winter, but often new growth sprouts reassuringly in the spring.
Some roses root more easily than others. You may read in books that it is "not worthwhile" to root your own rose plants from cuttings, because it takes them a good two or three years to make a large plant that blooms freely. On the other hand, it costs nothing. Some weak roses undoubtedly do better on a tough understock (the red climber 'Dr. Huey' is often used, or else some form of Rosa multiflora, with the fancy garden variety budded on these vigorous stocks) but it does no harm to try them on their own roots -- that is, from cuttings, and not budded on understocks.
We used to raise good plants of 'Radiance' from cuttings, and a friend of mine who grew only modern hybrid teas and floribundas always kept a cutting bed going. His failures were many, but every year he seemed to have about 20 nice new plants from cuttings to replace any gaps in his beds.
Many climbers root surprisingly easily and so do bushes of the China types. I rooted a three-inch twig of 'Slater's Crimson' that had been cut two weeks previously and carried around in a plastic bag in luggage. So it never hurts to try.
It is not at all too late to plant gladiolus corms. One year I planted them as late as the first of August and they bloomed all right. Normally, if you like these flowers at all (and many do not, being sick of them at flower shops) you plant a batch of the corms or bulbs in mid-March and keep planting them at two-week intervals through mid-July. This gives flowers from June till mid-October.
Blueberries should be mulched. Sawdust is commonly recommended. Sometimes, however, they are wanted as ornamentals in places where mulching is not feasible, and blueberries can flourish nicely without any mulch at all. I have one (the variety 'Earliblue') that has graciously grown over several years despite grass right up to its stems and that is heavily laden with fruit. This plant has been a favorite of the basset hound who licks the berries off when they are fully ripe. Fortunately the fruiting branches are now too high for her to do this and she will have to be content with a handful or so that we, and not she, have picked.
Nothing improves a gardener's restraint with fertilizers like killing a few plants by "feeding" them too well. I lost a whole batch of Japanese irises through too-generous applications of horse manure, even though these are great feeders. Manure from birds can also be overdone easily, and much grief can come from those liquid fertilizers bought in bottles and diluted with water as directed on the label. The trouble is the gardener does not believe one teaspoon to a gallon of water is likely to do anything fine, so he gives an extra glug or two. I have done so myself.
You may be sure the manufacturer is happy for you to use as much of the product as possible, so when he says "one teaspoon" or whatever, we should not use more. Also, any fertilizer should be applied when the ground is already damp, either from rain or by watering the day before fertilizing.
I see one difficulty with my Sturt peas from South Australia. They are desert plants, so I grow them in tubs of sandy soil. Every year they grow but never bloom. They abhor rain, by and large. They should be grown with glass protection from downpours, and theoretically one can devise some such thing in the garden. Peering at mine this week and musing how best to shield them from the weeping heavens, I saw half a dozen small slugs contentedly gnawing on the leaves. So high has the humidity been that the slugs were active two feet above the ground.
It is silly to mutter that these plants "do not do" with us, if we try to grow them in such a rain forest that slugs climb feet into the air. It would make more sense if mine had been protected by glass panes from the beginning, and this is hardly the time to start thinking of it. Many if not most garden disasters are of our own making, or at least of our own negligence.